Author: Al Ciampa

Perspective is everything.  As a health educator, I look at the body in terms of function.  If function is deranged, you may experience signs and symptoms.  “May” because slightly deranged function can be successfully navigated by the cell.  Beyond a certain threshold, “dysfunction” takes hold and the associated symptoms emerge.  Restoring function should be and is paramount for removing those negative sensations.

Metabolic function is common to every cell in your body.  It is how your cell maintains energy levels and performs its work.  However, different cells perform different types of work.  Neural cells collectively perform the task of cognitive function and system control.  Muscle cells perform the task of physical work.  Heart cells perform the task of a certain kind of physical work, i.e., pumping blood through your system. Liver cells perform yet a different set of tasks.  The cells of your vascular system too allow your veins, arteries, and capillaries change their posture and evolve to the needs of your body.  Your lung cells, kidney cells, splenic cells, osteocytes, adipocytes, red blood cells, pancreatic cells, epidermal cells… all the cells of your body have tasks to perform, and if there are in good working order, the sensations from your body will generally feel good.  Another way to say this is that you will not feel any negative sensations, however you define this.  You should not experience daily headaches, muscle pain, skeletal discomfort, itching skin, abdominal gas or bloating, etc, etc, etc.  You may not feel fantastic, but you should feel “poorly”.

If you are experiencing general pain or discomfort that has not been sensed since birth, then there is something amiss with your metabolism–the system in charge of maintaining the energy and supporting role in the assigned tasks.  If things get worse, and you begin to present with a cluster of symptoms, you may be diagnosed with a “disease”.  Which is nothing more than assigning a label to an previously observed and “understood” pattern of human condition.  The algorithm in response to your diagnosis that most medical specialists follow are couched in targeting your symptoms, allowing you to feel better.  Though necessary for many at the proper time, this tactic is not addressing and resolving the root cause–the source–of your discomfort: system dysfunction.

It should not be a surprise that if, for example, you are deficient at the cellular level of niacin, which is also known as the B-complex vitamin, B3, the cells and tissue throughout the body may or may not show the results of this deficiency.  In the brain, you may experience depression, anxiety, or compulsive disorder, or even suicidal ideation.  In the liver, you may experience high cholesterol or triglyceride levels (understanding that you may not literally “feel” this effect).  In the muscle, you may experience pain or low motivation to do work.  Certain glands may respond with hyper- or hypo-secretion of their respective hormones, possibly disrupting sleep or blood sugar levels, or the ability to thermoregulate.  Unexplained skin rashes, eczima, acne, etc.  Most every negative experience might be explained by cellular dysfunction–and this is the cheapest and most effective therapy with which to begin the healing process.

From the excellent paper, “Metabolic Correction and Physiologic Modulation as the Unifying Theory of the Healthy State: The Orthomolecular, Systemic and Functional Approach to Physiologic Optimization”:

To summarize, metabolic correction has three important biological actions: First, optimize cellular function by improving enzymatic efficiency; second, produce a pharmacological effect to correct abnormal cell function due to the biochemical disarray produced by the disease process and; third, increase energy production needed to maintain the organization and communication necessary for keeping the physiological balance vital for the healthy state. An optimum intake of micronutrients and metabolites, which varies with age, environmental factors and genetics, should correct metabolism and markedly improve health at a modest cost.

Food and nutrition are your first lines of attack.  If you feel absolutely terrible, please use properly prescribed pharmaceutical interventions for relief, but only as a crutch while you are maintaining your assault on the main front: restoring function.  Unlike the fast-acting response of drugs, nutrient restoration requires time and patience, a point that makes it an easy target for instant-gratification seekers.  Nourishment is not ineffective for disease and symptom relief because it takes time for fruition of the results.  Mitochondria are the center of your collective cellular system; feed them to feed yourself.

Even if you feel relatively fine on a day-to-day basis, improved metabolic function will result in improved performance on the track, in the field, at the gym, or during your office meetings.

Citation:

1. Gonzalez MJ, et al. 2018. https://isom.ca/article/metabolic-correction-physiologic-modulation-unifying-theory-healthy-state/

Is it too cold outside? Too hot? Are you hungry? Are you tired? Is the corner store too far to walk to? Do you essentially take the path of least resistance at every decision point in every day of your life?  This approach is probably disturbing your health.  Your body’s resilience to environmental encroachment maintains its integrity by being exposed to environmental encroachment.  It seems too simple a matter to even mention, but less apparent is that the opposite is true, and, I will repeat myself: if you seek to avoid the relative discomfort of environmental encroachment, your body will lose the ability withstand any changes in the environment.  At a cellular level, your body’s robustness is a result of simply asking it to be robust.

Have you ever wondered how people did not suffer before air conditioning and central heating; before roads and gas stations; before, dare I ask… smart phones?  Folks were at the whim of natural variations.  Imagine the wintertime.  Patches of snow spot the terrain outside of your window, near to here you are sitting comfortable, reading on your Kindle.  Perhaps the draft from an older window in your home drops the temperature just a bit, and it is that time just before the furnace kicks on to move some warmer air into the room.  You have been sitting idle for some time, and just then, you feel cold.  It almost kind of burns—an odd sensation from the lack of heat—while your skin puckers up with goose bumps, trying to keep out the cold.  Maybe you experience a lightening bolt sort of sensation down your back as your muscle involuntarily contract resulting in a shiver.  In that moment, the environment—the cooler temperature of the air surrounding your body—is asking, no demanding, your attention.  Two degrees higher and perhaps three minutes ago, you knew nothing of the impending assault on your body and mind.  What is this experience anyway?  The body is generating heat such that a temperature test would read about 98 degrees F or 37 degrees C.  Why is the surrounding air of 72 degrees F causing this onslaught of painful misery?  Why did is not occur at 73 degrees?  Why does it also not occur sometimes when it is much colder?

When this happens to me, I often think about the robust individuals of years past, traversing the continental United States from East to West in nothing but covered wagons or on horseback, exposed to the natural elements with no recourse if the situation grows even more sour.  Sub-zero temperatures seem to offer no boundaries to pioneering individuals while a rather warmed room of shelter is causing such a painful reaction from my body.  Sensations.  Feeling cold.  Feeling hot.  Feeling hungry.  Feeling tired.  Feeling the need to breathe.  Communication from your mind to your brain, via your body; compelling you to act; seemingly, in your best interest.  Act you will, trying to remove even the slightest sensation of discomfort by using conditioned responses: for cold, turn up the heater; for hunger, eat, and so forth.  As you do so, you cause future sensations to grow more or less intense in response to the same environmental signal.  For the easy example I have been banging away at: the temperature drops a bit, causing the above described sensations, and you run and increase the temperature on the thermostat, kicking on the furnace and releasing warm air into the room.  The sensation of “cold” quickly disappears, for the moment; but what has just happened is that you communicated to your mind that respite is always near.  Your mind, in turn, will reset the cue to signal to you that it is too cold to just an infinitesimally small degree of difference so that next time, you feel the sensations of cold at a warmer temperature.  This is a most important point; and this effect occurs over a wide range of phenomena; and it changes your physiology.

When you instantly seek comfort, always and constantly, cellular function changes such that you grow less resilient.  Smaller environmental changes now cause a greater response in sensation.  To keep with our example, you will feel colder at higher and higher temperatures.  This lost of robustness over many different signals is a decline in your health.  To regain health, integrity, and robustness you must start to get comfortable with being a little uncomfortable.  It requires mental focus, but it will move the needle in the direction you need it to. As your health improves, you will be less hungry, less cold, less infections will grab hold of you less often; you will breathe less, you will want less, you will consume less, your physiological and psychological function will improve, you will experience pain and hurt less; and very likely, you will find peace. All from progressively experiencing a bit of discomfort… feeling alive.

You’ve all heard the paraphrase, “he must have a fast metabolism, that’s why he stays so thin/lean”.  Well, let’s think about that.  The physiological definition for metabolism is: the net effect of all catabolic and anabolic reactions.  Doesn’t sound like a recipe for weight management.  Catabolic reactions are those that separate larger molecules, like proteins and fats, into their constituent molecules, like amino acids and fatty acids, respectively.  Anabolic reactions have the opposite effect, synthesizing smaller substrates into larger particles.  Like many products of nature, what you are left with is the net effect of everything you add plus everything you subtract.

Metabolism is essentially a set of chemical pathways.  Metabolic action serves essential functions of the cell, such as energy provision, creating structures, reducing structures, and cellular signaling.  (This last feature is most interesting.)  The chemical pathways that comprise metabolism are foundational to life itself.  Alterations to these pathways are now understood to contribute to disease and dysfunction.  In order to operate in the manner intended, your cells require delivery of the results of digestion and respiration.  If something isn’t present when needed, or if something is present that doesn’t belong, altered metabolism occurs.

Now, you don’t store calories, you store triacylglycerols.  (And you don’t actually “store” them, either.)  Triacylglycerols are fatty acids bound to form lipid droplets—fat.  Though very small, triaglycerols do take up space, and if you have enough if them together, you will need more space.  A calorie is the amount of heat energy required to raise one gram of water, one degree celsius.  We can argue that calories refer to food and then, I would at least see your point.  We can go further and say that you can have an excess of x amount of calories hanging around in the form of tricylglycerols, and then I’d ask you to think about what that means.  Why is the body accumulating excessive triacylglycerols?  Why is metabolic action favoring anabolism?  You might begin to see that it has nothing to do with the rate or “speed”.

Many folks only think of the word metabolism only in relation to the their leanness (or fatness).  Many others only think of metabolism in relation to energy provision and their ability to do muscular work.  Brain cells are in the business of controlling the system and of thinking—you know, brain work.  Blood cells are in the business of delivering substrates and molecules to and from cells.  Adipocytes (fat cells) are in the business of acting like a sink for triacylglycerols.  Muscle cells do physical work, and so forth.  The combined catabolism, anabolism, and energy extraction of the same substrates—and the cellular signaling of these actions—is in effect used for different things in differing types of cells.  Why is the body accumulating excessive triacylglycerols?  Because the metabolism of one or more tissues is altered.  And this has nothing to do with heat.

What is causing this system dysfunction?  How do we resolve this dysfunction such that the body will liberate its adipose tissue mass and properly manage energy regulation?  A health educator would suggest a change to your personal behaviors in such a way that restores system function.  Count calories?  Hardly.  Yes, there is documentation of a male who lost body fat while eating a hypocaloric diet consisting of only Twinkies.  That unlucky individual’s body does not wholly express system dysfunction through adiposity.  I’d like to hear what a conversationalist he was during this time period.  Don’t be fooled and waste your time.  Remove the environmental encroachments to your system, and add those system-friendly practices like proper eating and physical activity.

We tend to lack a focus on the quality of food.  If the metabolic pathways do not have all the raw materials they need to function properly, you will be in trouble.  As an educator and researcher, I see the body through the lens of chemistry. What effect do energy drinks, convenience foods, beer, and other chemically-ladened foodstuffs have on metabolism?  It’s not the speed of the metabolism that counts, it’s the robustness of it.

The earth doesn’t care about your success and neither does the guy down the street.  To be honest, there isn’t a need for more humans, so even from nature’s perspective of species survival, you’re not very important.  You are important to you and to those around you.  Take some interest in your own function.

Supporting Literature:

1. 1. Chandel, N. (2015). Navigating Metabolism. ISBN: 978-1-621821-29-8

Loading up your walks, or hiking, is a great way to get out and experience nature while getting your aerobic exercise. Here is the link to my article about hiking on the StrongFirst website. Please begin any new discussion in the comments section below.

The Kettlebell Snatch Lift.

The KB snatch should not be practiced until you have accumulated ample time practicing the one-arm swing. If you have run through the program in the book entitled, “Simple & Sinister” (S&S), then you have built your one-arm swing by introducing the hip hinge, and then progressing to the short-stop drill, bracing, the deadlift, and the two-arm swing. It is a good idea now to review this book before you continue on to the kettlebell snatch lift. The snatch begins in the same hinge position as the swing but then veers off on its own trajectory. The load will not float out in front of you, but will be fixated overhead atop a locked arm. Where the swing is projection of horizontal hip force, the snatch is a projection of vertical hip force—it is more like a jump to standing plank, rather than the swing’s punch to standing plank.

The snatch has been called the Tsar of the kettlebell lifts and for good reason: It seems to have few gaps in promoting training adaptations. You can use it for cardiovascular development, overhead strength development, shoulder health and mobility, postural improvement, and of course, leg & glute strength and power development. It has proven to maintain if not increase one’s overhead press (the one-arm kettlebell press). It has proven to “open up” the shoulders and improve scapulae positioning in users. It has proven to build legs that won’t quit on even the steepest of hills. It seems to be the one-stop shop for physical enhancement—but you have to use this tool properly.

In the Hardstyle kettlebell tradition, the snatch was and is a lift that is taught and tested for technique, but it is also used as a test of a student’s mettle: The 5-minute snatch test. This event asks that you complete 100 snatches in less than 5 minutes, with your “snatch-sized” kettlebell. For the average male, this load is 24kg or 53lbs. For the average female, this equates to 16kg or 35lbs. These are loads that are not very heavy, but the speed of action and overall volume add up. The kettlebell snatch, to date, has been mostly used as a light to moderately-light loaded conditioning tool. Kettlebell forums are filled with users that simply do not snatch heavy weights. In the A+A protocol, we will be using a moderately-heavy to heavy load—some of our male participants routinely use the 40kg kettlebell as their go-to workload. This is wholly different use for this tool than tradition has molded.

Before we attend to the snatch lift, and because the learning curve of the snatch begins where the one-arm swing’s learning curve ends, so let me review:

The One-Arm Swing.

The one-arm swing is a ballistic and unilateral hip-extension movement. It is one of the most athletic but safe exercises you can practice, providing a lot of return for the time and energy invested. The swing is a fantastic tool for developing high levels of strength and endurance. A properly performed kettlebell swing is a violent but graceful display of the incredible power of the hips. However, the swing requires considerable time and practice to master.

There are two positions to the swing: the hinge (an athletic position), and the standing plank. The rest of the lift is to move explosively between the two. Understand that many people are at first unable to properly move into the hip hinge. Moreover, because of our lazy and sedentary society, most people do not and/or cannot, stand correctly (re: standing plank). The hinge is the bottom position of the swing. This position of acute hip flexion combined with “minimal-ish” knee flexion, while maintaining a neutral spine is not often seen anywhere else in sport or exercise, and even less so in the typical daily routine of life. The body adapts to that which it is exposed to, and no more, so true beginners rarely find themselves capable of a competent hip hinge. Compounding this issue of poor positioning, the loading on the back swing occurs with increased velocities, i.e., the bell is speeding downward, forcing you into the hinge. A heavy dynamic eccentric loading is not a good idea if you cannot move into this position naturally.

The hinge requires a bit more than the common cue to, “sit back”. It is to do so with a stiffened and properly curved spine and slight knee bend. In a body that has restrictions, these two postural requirements of the hip hinge compete for control of your pelvis. Minimal knee flexion causes the hamstrings to lengthen as the hips move further into the hinge. Shortened or weak hamstrings and a lumbar spine with a neutral arch pull on the pelvis from opposite directions. Something must give way—either the knees or the spine will be forced into flexion, or the pelvis will be forced into what is called posterior tilt. Google it. These errors in posture are to be avoided, but if your chassis is in a state of degradation, no amount of wishing will correct them. Take the time to drill a hip hinge with light or body weight loading. The standing plank too is an active and for some, a difficult posture. The pelvis must be neutral, meaning that it is not tilted in any direction. The scapulae must be positioned slightly to the rear, and depressed down, also known as “packing the shoulders”.

Do not underestimate your current inability to hinge correctly as having the potential to cause you pain or injury if you fail to heed this warning and jump directly into swings. Any “illusion of strength” developed through the typical weight room program of controlled, stabilized, and segmented exercises will quickly dissipate against the swing. We are here at this juncture to rebuild your “chassis”. Once your body adapts, and your hamstrings toughen up in response to the forces produced by the swing; and you will know what strong and resilient is. For now, just practice your hinging… ego aside.

I will advise here, again: Please review the material in S&S, and do not get started practicing snatches until you are ready.

One-arm Swing Performance.

The height of the bell is meaningless; concentrate on an explosive hip snap, and projecting power forward. This is the quality that we are concerned with: You are purposefully wasting energy, power, and effort—this is Hardstyle. Keep your body’s weight back on your heels and maintain a very tight plank position. Find the balance between your body weight and the swinging bell through your practice. End added text.

• Take a stance about shoulder width, toes cantered out, about a foot behind the kettlebell
• Sit back into the hinge, unlocking your knees, grab the bell, and lean it towards you
• Tense up hard—pack the shoulders, brace the abs, squeeze the glutes, grab the ground with the feet and get ready. You will be looking at a spot on the floor about 20 feet ahead of you.
• Shift your body weight back onto your heels as you forcefully “hike” the kettlebell up and back between your legs, grabbing a snort of air through your nose—compress the spring of the hinge position
• Then, as you exhale a bit of air, quickly and forcefully snap your hips into extension, literally throwing the kettlebell forward across the room!
• The bell will arc upward to about chest height, as your arm pivots about your shoulder
• Let the kettlebell “float”, weightless for a moment, at the apex of the arc that the swing creates in front of you
• As the bell falls under gravity’s influence, hold the plank as long as possible, then guide the bell back into the hinge position, keeping its return path high up near your crotch—once again, compress the spring
• Return the kettlebell to the ground after a final back swing by gently parking it as you originally found it.

“Floating the bell” in the plank does not mean that you are completely relaxed. Create a tight standing plank and stay connected to the bell. Use abdominal pressure and that sharp but short exhalation during your hip snap to tighten your plank:

• Your feet should be rooted into the ground
• Your knees should be locked and “pulled up” (squeeze your thigh muscles)
• Your pelvis should be parallel with the ground and out under your head
• Your gluteal & abdominal muscles should be tight, and trunk hollowed out
• Your working latissimus dorsi (lat) should be engaged—connecting your arm to your pelvis
• Your hand and arm function as a hooks only
• Your neck is relaxed, holding your head neutral; and your eyes are fixed on the horizon

If you think, “squeeze grip, abs, lats, and glutes”, everything else will fall into place. That all said:

The most articulate author cannot describe this movement in a manner that will allow for even a decent performance—so, safety first: Please find a qualified instructor.

Many people have a lot of trouble when they first start practicing the swing. Let’s just have you get the movement pattern down and be patient. Always use an appropriate load. You are now just several years from mastering this very basic and foundational exercise. The swing should not be something that you quickly learn then, simply “do the reps”. Every rep of every session is an opportunity to further improve your swing: Your position, your tension, your balance, your control, etc. Stay mindful. A highly crafted and expertly performed swing is infinitely more safe and effective in stimulating the desired training response than the immature swing of a beginner. Become a “martial artist” of the swing, and, go practice.

The Overhead Lockout.

Once you have the one-arm swing dialed in, introducing the overhead lockout is probably the best way to teach and transition into the snatch. The mechanics of the swing are similar to those of the snatch, but especially the lockout position is new and different. The overhead lockout will teach this position as well as check to see if you have the shoulder mobility to be practicing snatches in the first place. Moreover, in my experience, a student that has practiced swings and overhead lockouts naturally brides the gap between them—a snatch—with very little instruction.

The overhead lockout is as simple as it sounds: Put a kettlebell at an arm’s length over your head, and hold it there—better still, walk around with it up there. Start with a lighter kettlebell than you think. To get it overhead in the safest way:

• With two hands on the handle use your hip extension (as in the swing) to bring the kettlebell from the ground up to your chest—I’m not here to teach the clean, but this will work too
• Transition your non-working hand to the body of the kettlebell
• From the front of your chest, either press with two hands or “jump” the kettlebell to the lockout position overhead
• Remove the non-working hand from the bell and use this arm for balance, if necessary

It is important how you organize yourself underneath the kettlebell. First, have someone check you from the side (do not use a mirror) and ensure that your shoulder is fully open, your head is not jutting forward, and that you are not compensating for your lacking shoulder by leaning backward. Find a qualified instructor if necessary, as this very important detail is beyond the scope of this article.

Next, rotate your thumb toward the rear so that the palm is your hand is facing (or almost facing) the side of your head. Then, pack your shoulder, or pull the kettlebell down toward your trunk without bending your arm. You should feel a strong latissimus dorsi contraction—this is the platform upon which the load will sit. Squeeze your scapulae together, behind you.

Do lockouts often during and/or after your swing practice. Practice the static posture until you’re confident, then, go for a walk with the bell overhead. Start with very light weights and increase them gradually over time.

The Snatch.

The snatch is a hinge movement that throws the kettlebell from the hinge position of the swing to the locked-out position of the get up. I like to introduce this ballistic movement only after the individual has a crisp, snappy one-hand swing, and a solid finish position in the get up. Note: I teach novices to the swing a hinge position that has very minimal knee flexion. As the student becomes hardened and the muscles are able to better relax, I move their hinge position to one with a bit more knee flexion—not unlike an athletic position. This is the start point for the snatch’s hinge.

Begin the snatch about a foot behind a parked bell, hinge back, grab the handle with one hand and lean it toward you—nothing new here. Explosively hike it between the legs, but unlike with the swing, you will slightly raise your trunk and bend your knees a bit. This grants you a hinge position that is better suited for vertical projection. It does require a bit of practice, especially since you have likely patterned a slightly different hinge. Practice will reward you.

Now, instead of projecting the bell forward, you are going to project it up. After an explosive hip and leg extension, guide the bell up by sharply pulling the elbow to the rear. Your hip and leg action will cause the bell to initially move forward, but this arm/elbow action will project it up. When the bell gets near head height and feels weightless, punch underneath the bell, flipping over, and lock it out overhead. I cannot stress enough that your shoulder, elbow, wrist, and hand need to be in a properly packed & vertical position before the weight of the bell drops into the lockout. You need to throw the bell hard out of the hinge, and get in position and tight before you catch the bell in the lockout. If you focus on tight glutes and abs, and squeezing your shoulder blades together, you’ll be ready for the catch.

It is the jump action of the hip and legs that launch the bell with enough force that it climbs into the lockout—the arm and shoulder should not be used to pry the bell into the lockout. You will know when you get this right, and you will also know when you get this wrong—do not ignore this small but very critical detail of the snatch.

The drop from the lockout of the snatch is also quite different from the drop of a swing. For one, the weight of the same bell will feel heavier when dropped from a higher vertical height into the hinge. You will also want to keep the trajectory of the bell close your body. To being the drop, lean back slightly while you yank the handle of the bell forward and down. This will flip the bell and start a relatively vertical drop. When the bell is at about head height, let your hand come slightly away from the handle and regrab it in the hand position you’d like when it hits the bottom. This takes a lot of practice to master but it will save the skin on your hands. You only need a firm grip on the handle in the hinge when snatching. After the throw and until mid-way into the drop, you don’t need to be vise-gripping the bell.

Still on its way down, when it passes your chest, you can now come back forward and set up your hinge. You need to drive the bell into the hinge—don’t let it pull you there! Now is the time for a vise-grip while you set your hips back, bend your knees, and guide the bell between your legs until it gets behind you. You’ll notice an increased compression of your spring in the hinge position with a bell being dropped from overhead. Use this to your advantage and jump the bell into the next snatch.

The skin on the palms will be challenged with the snatch. Swinging will harden the palms but once you begin to snatch, you will understand the meaning of callous. The additional distance and velocity that the bell descends in the snatch causes lots of friction during the “catch” in the hinge. The best way to navigate this is to attack the hinge—really drive the bell back deep so the forearm ends up high near the crotch. Also, take care of your hands … use a pumice stone to keep the calloused skin flat and even with the rest of the palm. That said, you’re just going to have to build volume and load slowly and let your hands adapt. During any session, don’t let your hands tear during snatches. Once you feel the skin burn and stretch, end the session and live to fight another day. The palms heal very quickly.

I should not have to say this at this point, but:

The most articulate author cannot describe this movement in a manner that will allow for even a decent performance—so, safety first: Please find a qualified instructor.

Supporting Literature:

1. Tsatsouline, P. (2013). Kettlebell: Simple & Sinister. ISBN: 978-0-9898924-0-7

Alactic & Aerobic (A+A) Training.

The A+A protocol uses the Alactic energy pathway of the cell to fuel the physical work of the repeat, or set. It then uses the Aerobic energy pathway to replenish the high-energy substrate of the alactic pathway, creatine phosphate, during the recovery period between repeats: Hence, “A” + “A”. Organizationally, the sessions of an A+A protocol consist of a variable number of repeats (NR), or work periods to be performed, each followed by an adequate rest and recovery period. The total volume of each session is the main variable. This protocol should only be used with high-power producing movements, and the kettlebell (KB) snatch lift one of the most effective.

In practice—what you do in the gym or your garage—is choose a high-powered movement and execute it with a purpose for 6-12 seconds, depending upon your current fitness. You then rest and recover for as long as is required so that you can again work at a high output. This can be as long as 2-3 min, or as little 1 min, again, depending on your fitness level. If you look at the diagram below, we are trying to employ the alactic system to fuel the work, and the aerobic system to fuel the restoration of the alactic system—it is during the recovery period that the aerobic system is challenged, and the overall duration of the session makes a great difference here.

The main variable to manipulate is the duration of each recurring session. An average of 30 repeats seems to work best, and you almost never want to actually complete 30—ebb and flowing under and over this average number will lead to better adaptation.

The protocol is blue-collar work through and through: punch in, do your work, and punch out. There are no “gym” goals; the only goal is to make you a stronger and more enduring you. It is work that is intense for short period of time, followed by a rest period while you prepare to do more work of the same kind. Conjure the images of loading a truck, chopping wood, farming, working on your own home improvements—you move to accelerate loads, then recover during your body weight movement back to the next load. The relatively short work period combined with a sufficient recovery period, in the context of extended sessions is what allows A+A training to increase strength-endurance while improving health. This method of training increases your biological resiliency rather than depleting it.

Repeats are strategically prescribed to allow a sufficient amount of recovery during the rest period so that you are able to go into the subsequent repeat performing at a high power level. If you believe the energy system science/philosophy and debates, repeats can target specific energy systems, causing them to adapt in positive ways, i.e., improved function. A+A repeats maintain the work period at a high output, and not continue too long such that output falls off. In biochemical speak, A+A avoids too much glycolysis, or, lactate-producing work.

Biochemistry.

All cellular fueling is accomplished by releasing the free energy contained within a molecule called, adenosine triphosphate (ATP). The ATP molecule is the energy currency of the cell: It is the money used to purchase energy for fueling work. Work does not just refer to muscle activity and movement; every type of cell in your body must accomplish physical work on a microscopic level, such as pumping ions across gradients.

The ATP molecule is a high-energy phosphate compound that can be chemically acted upon, producing different substrates while releasing energy. There is a small pool of ATP within each cell that it uses to fuel work. However, this pool is quite small and can only provide fuel for a short time. As your cell does work, the pool level drops but there are several systems in place that create ATP molecules from other substrates, restoring the pool level. The professional literature suggests that under no circumstances does the pool level drop below about 70% of its resting level. Fatigue sets in prior to this through many mechanisms, as running out of ATP would result in the death of the cell.

Above is a simple graphic of the ATP molecule. Without exploring too far into chemistry, you will note the three phosphate groups to the left. There is a lot of energy binding that last phosphate group to the package. What is known as cleaving in chemistry, this last phosphate group is removed from the molecule, releasing the energy stored in to the environment.

This splitting of the ATP molecule, called ATP hydrolysis, is the act of cleaving off this phosphate group. This can occur when ATP chemically reacts with a water molecule. The rate of this reaction occurring can be increased through the use of an enzyme: ATPase. Enzymes are proteins that can interact with atoms and molecules, speeding up the rate of their reactions but without changing the products of that reaction.

In this case, ATPase acts on ATP and a water molecule and converts them into:

• An adenosine diphosphate molecule (ADP)
• An inorganic phosphate compound (P_i)
• Hydrogen ions (H+)
• Heat
• And the goal: “Free energy”

Here is the reaction:

Note the hydrogen ion to the right of this chemical equation (in black). This is significant, as increasing the hydrogen ion content of a solution reduces its pH level, or makes it more acidic. This acidity—this increase in cellular acidosis—is likely the most dominant cause for a decrease in energy system output. The cell is placed in a state where it is unable to replenish ATP molecules at a rate that maintains a sufficient ATP pool level—one of the several ways that can lead to fatigue. Not unrelated, increased acid levels degrade proteins, the stuff you are made of. The three-dimensional shape of the protein molecule makes it very sensitive to hydrogen ions. On a systemic level, chronic acidosis might significantly contribute to ill-health and dysfunction of many varieties.

The raw materials needed to create new ATP are already present in the cell: the ADP and P_i molecules. Recall that these ingredients are formed during ATP hydrolysis, and the cell has systems in place that effectively recycle ADP and P_i back into ATP. Clever and efficient—energy is the missing ingredient in this biological stew.

The energy that is required to form new ATP molecules comes from the food we eat and/or (as in case of starvation) the physical structure of our bodies. The cell has three energy systems, or pathways, that we know of. These sets of chemical reactions take the products of digestion—the macronutrients in your food—and catabolize them, or break them down, harvesting the energy from within those molecules and using it to provide ATP with it’s “jolt” when rejoining ADP with P_i.

The energy pathways are known by several different names, depending upon the university you attend, the country you live in, or the author you are reading. A short list of these follows:

• The PCr energy system, also known as the alactic pathway, the phosphagen system, or the ATP-PCr system
• The glycolytic energy system, also known as the lactic pathway, glycolysis, or (erroneously) anaerobic glycolysis
• The oxidative pathway, also known as oxidative phosphorylation, the aerobic system, or mitochondrial respiration

The first two systems are classified as anaerobic, because they create ATP without the use of oxygen. The final pathway is defined as aerobic, because it requires oxygen to create ATP.

Alactic Energy.

The PCr energy system is not a “system” at all but a very simple chemical reaction that acts on a phosphocreatine molecule (hence the name of the pathway). Note the following reaction:

The creatine phosphate molecule has a high-energy phosphate component it. This phosphate is cleaved from the molecule, and then combined with ADP and a hydrogen ion. If you have been paying attention, you will note that this process actually alkalizes the cell (increases its pH) because it removes hydrogen from the environment. But not to such a degree that it is worth anything but a mention here. However, for single-celled creatures, this strategy could be very important!

Like the ATP molecules that comprise the ATP pool, creatine phosphate is a substrate present in the cell, but in very short supply. Remember that an alternative name for this pathway is ATP-PCr. This title is simply lumping the ATP pool together with the above reaction. This first pathway of generating ATP is quick and simple—remove energy from phosphocreatine and combine it with ADP and H+.

This is where the traditional textbooks stop. There are two additional cellular reactions that Baker, McCormick, and Robergs include as part of the PCr system:

Dr. Keyser tells us that increasing ADP levels and decreasing ATP levels in the cell lead to a decreasing ATP:ADP ratio; and this can also lead to fatigue. Increasing ADP level causes adenylate kinase to go to work on ADP, reforming ATP and creating a molecule called, adenosine monophosphate (AMP). This can be seen in the first reaction.

In the second reaction, AMP combines with hydrogen to form inosine monophosphate (IMP) and ammonia (NH4), which the cell, and body, must get rid of.

The point in introducing these additional reactions is:

• AMP activates some of the enzymes in glycolysis (the next pathway we will discuss)
• These three reactions together may produce enough ATP to power both resting level activity, and supra-resting level activity, possibly changing how we currently think about bioenergetics
• These two additional reactions suggest that PCr system function might also keep ADP, AMP, and H⁺ levels down, helping to prevent fatigue

This system is very powerful, but with little capacity. It can restore ATP quickly, but only in small amounts. It is thought by exercise physiologists that this system is exhausted after about 10-15 seconds, but can power the most intense of muscular contractions, like sprinting and heavy weightlifting. It is important because it is used in most sport applications: Intermittent and short high-intensity bouts of activity repeated after longer intervals of active or passive rest, describes many of the games that we play. Think about what an individual actually does in basketball, American football, soccer, ice hockey, etc. A lot of jogging/walking separated by very short but very intense sprints/movements… this energy system plays a very important role in short and intense activity, and its ability to recover is central to success in sports.

Glycolytic Energy

The next energy pathway is glycolysis, which literally means splitting of sugar. This lactate pathway acts only on sugar molecules (glucose or glycogen)—so, we are now using the energy from the food we eat to fuel cellular function. As compared to the three, single-function chemical reactions of the PCr pathway, glycolysis is a much more complicated series of reactions, and the chemical reactions of the lactate system work on glucose in a linear manner.

Glycolysis removes the energy from either the glucose or the glycogen molecule (the storage from of glucose) and uses it to form ATP. The main molecular product of these reactions is pyruvate; or lactate, depending upon which scientist’s idea that you purchase. There are two phases to glycolysis: The preparatory phase, and the pay-off phase. To keep things neat and easy to understand, I have included only the molecules being acted upon (denoted by the blue arrows), and the required/resulting substrates of several individual reactions (denoted by the black arrows) in the figure below. The preparatory phase creates two molecules of glyceraldehyde 3-phosphate that can be used in the pay-off phase. In this first phase, ATP is required for this conversion—two, if we begin with a glucose molecule, and one, if we begin with a glycogen molecule. Read that again. You can see this on the top left of the figure.

In the preparatory phase, ATP hydrolysis adds ADP and hydrogens to the environment, twice as much if using glucose, which may lend to the idea of not completely foregoing starchy carbohydrates. It is the pay-off phase of glycolysis that creates ATP. Through several additional chemical reactions, each of those two glyceraldehyde 3-phosphate molecules is converted into one molecule of pyruvate. You will note this in the figure down the middle of the pay-off phase with the corresponding reactions.

A positively charged molecule, nicotinamide adenine dinucleotide (NAD⁺) and an inorganic phosphate molecule is needed to convert glyceraldehyde 3-phosphate to 3-biphosphoglycerate. As a result of this reaction, NADH (the reduced form of NAD⁺) and a hydrogen ion are formed. The reason this is pointed out will become clearer later. In the next reaction, an ADP is used and we get our first ATP. The next reaction down produces water; and the final reaction uses ADP and H⁺, and produces our other ATP molecule.

The total yield for glycolysis is:

• 3 x ATP
• 2 x H⁺
• 2 x pyruvates
• 2 x NADH
• 2 x water molecules

…unless you begin with glucose, then the result is “2 x ATP and 1 x H^+”, and everything else is the same. So, you not only create less ATP through glycolysis when using a glucose molecule, but you also introduce additional acid to the cell.

The glycolytic pathway has less power than the PCr pathway, but it has more capacity. That is, it can’t peak as high in production of ATP, but it can do so for a longer period of time. You can see in the figure below how glycolysis (the lactic acid system) burns out around the two-minute mark when engaged in all out activity from rest.

Being a very ancient energy pathway, the one that allowed animal life to begin, glycolysis is actually a very inefficient way to produce energy—only 3% of the available energy is extracted from the sugar molecule. But, nature has adapted to this problem…

The Mitochondrion: Oxidative Energy

The mitochondrion is thought to once be a separate organism from the cell and the entire reason that multi-cellular animal life is so prolific today. In a powerful example of biological symbiosis, the mitochondrion feasts on pyruvate, lactate, fatty acids and hydrogen electrons, and produces CO2, water, and ATP. The mitochondrion has its own structure, membrane and DNA. It can replicate itself in a process similar to asexual reproduction, divorced from the activity of the eukaryotic cell within which it resides.

The medical literature has been revealing the association between the health of this “organism” and that of the host organism—you! You might be reading this article for a different reason, but you should be extremely interested in the health of your mitochondria.

Inside the mitochondrion is where the magic happens: Oxidative phosphorylation. This is a very complex system of ATP restoration that we likely do not fully understand. It occurs in two phases: The Citric Acid Cycle, and the Electron Transport Chain. Also known as the Kreb’s cycle, the citric acid cycle is a series of eight reactions that is spun through twice. The feeder molecule for the citric acid cycle is called acetyl CoA and it is the only molecule that this system can work on, so whatever the input—fatty acids, lacate, pyruvate, ketones—they all must be converted to acetyl CoA first. It’s simplistic to look at the citric acid cycle as a preparatory phase for the electron transport chain (ETC), but it fits with the observations. What the citric acid cycle does is harvest hydrogen protons and electrons, and the associated energy, for use in the ETC, where ATP is formed.

You can see in the above figure that NAD+ is required to carry the hydrogens to the ETC. Recall this function from glycolysis: NAD+ are the carrier molecules for hydrogens, and without enough NAD+, none of these systems can function. NAD+ might be the one very important substrate that few exercise scientists are talking about—it is effectively the bottleneck of the energy systems. When oxidative phosphorylation backs up, anaerobic metabolism must make up the difference, or movement intensity must drop off. The “fix” to maintain anaerobic respiration—which means to free up more NAD+—is the formation of lactate.

The ETC is where the pay off is. Every resource that I have read discussing the ETC uses terms like, “seems to”, “this suggests”, and “this or that may occur”, so let me state now that it is likely we have little idea what is actually happening in there. That said it seems that within the mitochondrion, there are two compartments separated by a membrane. Along the membrane are a series of structures, called cytochromes, and pumps, similar to the ion pumps of the cell membrane. The electrons delivered to the ETC by NADH move down the cytochromes in a train-like fashion, one to the next with a beginning and an end. Each relocation of an electron transfers some energy. Some of this energy is used to pump protons, also delivered by NADH, across the inner membrane, setting up a gradient. This gradient results in stored electrochemical energy, a form of potential energy. This energy can then be used to synthesize ATP molecules, by phosphorylating ADP, or adding an inorganic phosphate to an ADP molecule.

You might be wondering how oxygen fits into this schema… well, when electrons are added to a molecule or atom, it is called “reduction” and when they are removed from one, it is called “oxidation”. The cytochromes of the ETC act like atoms or molecules in this case, and function similar to a bucket brigade. Which looks like this:

Just like the firemen of the past in this picture, the cyctohromes hand the electrons to each other, so, a cytochrome has to hand his electron off before he can grab another. This oxidation-reduction reaction series continues on until the last cytochrome has his bucket of water, I mean, electron. This cytochrome would remain in this reduced state if there was no fire to dump his bucket on—this is the function that oxygen serves. O2 acts as the last man on the bucket brigade line, accepting the electron from the final cytochrome so that aerobic respiration can continue. Coupled with the protons that are diffusing back across the inner membrane in the phosphorylation process, the hydrogen atom is reformed, but in the water molecule: H2O.

It is ingrained in our language, at this point, to say that aerobic metabolism is limited by the availability of O2. That aerobic means, “with oxygen”, does not mean it is the governor of this system. It is probably not a lack of O2 (however much it may contribute) that causes you to outwork your aerobic system and move to using primarily the anaerobic system for output. Again, it is far more likely that it is a lack of NAD+ to carry hydrogens where they are needed. Unlike the media would have you believe, O2 is plentiful in our atmosphere, lungs, blood and tissues (in otherwise healthy individuals).

In summary, all substrates and foodstuffs are converted to acetyl CoA within the mitochondrion. Acetyl CoA is then run twice through the citric acid cycle in the mitochondrial matrix, extracting hydrogen protons and electrons for the electron transport chain. The ETC is a bucket brigade that collects the potential energy from the hydrogens and uses it to create ATP. The hydrogens are then passed on to oxygen molecules and form water. The oxidative system results in a rather “clean burn”: ATP, carbon dioxide, water, and heat. This is the beauty and magic of nature: far before we were able to look and see the mechanics of mitochondrial energy production, we built dams across rivers and used the potential energy of the weight of moving water to crank turbines which then created electrical energy. In very much the same way, the mitochondrion uses the potential energy of the weight of moving protons to crank a turbine and create ATP. In fact, this turbine is the smallest known “machine”.

The ATP yield from this process is 32-38 molecules depending upon what textbook you refer to. This grants you 34% of the energy from the original glucose molecule, as compared to the 3% extract from glycolysis. The remaining 66% of the energy in sugar is transferred as heat.

The “Lactate System”.

The quotes are up there because I don’t believe that generating lactate from pyruvate is conventionally understood as a system. Remember the two pyruvate molecules as a result of glycolysis? If there is too much acid hanging around, the pyruvate molecule can accept two hydrogens and convert to a lactate molecule. In the figure below, we see that one of the hydrogens is received from a NADH molecule, reducing it back to a NAD⁺ molecule. This is thought to allow glycolysis to continue… remember that NAD⁺ is required to receive a hydrogen ion as part of the first reaction of the pay-off phase.

Forming lactate functionally reduces the pH concentration of the cell, is a mechanism for glycolysis to continue to function, and creates a molecule that can be shuttled out of the cell for use elsewhere. Moreover, lactate can also be shuttled into the mitochondrion to be converted to acetyl-CoA and used to produce ATP. Is lactate production a buffering strategy, or is it meant to allow glycolysis to continue? Probably both.

Lower blood lactate levels during exercise is associated with anti-glycolytic training and less of a biologic cost; higher blood lactate concentrations is associated with the opposite effect: Higher biological cost and increased stress levels.

Energy System(s) Interaction: Muscle fiber types.

It is difficult to have a discussion about energy system interaction without discussing muscle fiber types—so let’s begin there. From a practical standpoint, this is all that matters here.

Muscle tissue consists of many types of cells, or fibers. These fibers are known as fast twitch—those that can produce a lot of force; and, slow twitch—those that cannot produce a lot of force. Although science has mapped at least three different twitched fibers, if you are familiar with biology, it is far more likely that there are many speeds of fibers that exist on a continuum, from slowest to fastest. (Note that to my knowledge, this last statement is not supported by research). This continuum might look like this:

Slowest >>> Slower >>> Slow >>> Fast >>> Faster >>> Fastest

The slower fibers are more aerobic, meaning that to a major extent, they are structured to preferentially produce force with the use of oxygen. The important qualities of an aerobic muscle fiber are:

• It depends upon oxygen to properly function
• It is not capable of producing a lot of force
• It has a lot of stamina

The less aerobic a muscle fiber is, the more it depends on sugar to create force. These faster acting, anaerobic muscle fibers have the following important qualities:

• They require glucose (or glycogen) for function
• They can produce a lot of force
• They do not have a lot of stamina

Muscle fibers are recruited in a particular way: From the slowest (weakest) to the fastest (strongest), based on the needs of the action. So, easier movements recruit the slowest of fibers, and most forceful movements will recruit all the fibers on the continuum. I.e., walking will recruit the slowest of fibers: Sprinting, the fastest (as well as the slower ones). The point is:

The main driver that determines whether an activity is aerobic or anaerobic is fiber type recruitment.

I think that this point is lost in common energy system discussion. An activity is more aerobic or anaerobic based on the fiber types that are available at the time of movement. Consider the vast system of outputs in this respect:

• If you begin mall-walking, the slowest fibers are recruited and the activity is mostly an aerobic one; however, to actually get your started, there is an anaerobic “boost”
• If you pick up the pace to a semi-brisk walk, there may or may not be a boost of anaerobic metabolism based on the strength and endurance of your slower muscle fibers (in the extremely detrained or untrained, this already can be a mostly anaerobic activity)
• If you push the accelerator to the floor of your walking gait, chances are your slower fibers and so the aerobic pathway can cover this action
• If you break into a slow jog, the sharp increase in total force production required will no doubt enlist faster fibers, increasing anaerobic pathway involvement
• Depending upon your training state and the duration of movement at this point, your slower fibers might be able to cover down on your jog
• If you continued to jog at this slow speed, when your slower fibers powering this activity fatigue, faster fibers will cover down, causing the activity to be more and more anaerobic as you move forward (this can be seen on a heart rate monitor, as it begins to grow higher and higher)
• If, however, your slower fibers can endure, you will remain mostly aerobic
• If you hit hills or turn into the wind, and want to maintain the same speed, faster fibers will be recruited, temporarily increasing anaerobic metabolism
• If you speed up, faster fibers again must be recruited to cover the additional force production cost
• At any point that reduce the force production required, i.e., you slow down; and your slower fibers are not fatigued, you will be more and more aerobic
• And this will go on and on…

Let’s look at this from the perspective of high force production from the onset, say the 5-minute snatch test with little-to-no warm-up:

• The faster fibers (but probably not the fastest) will be recruited, making this a wholly anaerobic event
• As these faster fibers fatigue, the fastest fibers will begin to be recruited
• As these fibers fatigue, the only fibers left are slower; making the event more and more aerobic as time goes on
• If these slower fibers are not very strong, you may have to stop the event all together; if they are, however, your pace and intensity will simply have to decrease
• If you pace this properly, the fastest (or fast”er”) fibers might be able to recover enough during the activity, which allows for a sprint to the finish!

Recall the chart above… it is a pretty good representation of the how each energy pathway works in isolation. However, they do not work in isolation; they have overlapping sectors of fire. This means that even in the same muscle fiber, aerobic and anaerobic systems are working together to fuel movement. Moreover, due to the above explanation of fiber type recruitment, the energy systems will also exchange duties as the overall primary energy pathway as you speed or slow the acceleration of your movement. With proper training, you can increase the strength of your slower fibers and increase the aerobic capacity of your faster fibers, and this is the core of strength & endurance training.

Oddly, aging and a sedentary lifestyle tend to harvest the faster fibers and reduce the aerobic qualities of the slower fibers, leaving the sedentary older adult with weak, sugar-burning muscle tissue. This explains a lot of the physical performance problems observed that are associated with the aging population. To some extent, strength training will also increase the endurance of the faster fibers and endurance training will increase the strength of the slower fibers. There is no reason, at this point, to prescribe one or the other interventions: Either one will stimulate positive adaptations in both strength and endurance. Especially with the aging and sedentary population, a physical training protocol that both improves the strength and endurance of all types of muscle fibers is warranted.

The A+A protocol falls under a larger umbrella of “anti-glycolytic” training that targets exactly the above idea, resulting in improvements in both strength and endurance while reducing the stress and biologic impact of the training sessions. This leaves you fresh to deal with the other tasks in life without having to drag you’re a** through the rest of your day.

Supporting Literature:

1. Baker, McCormick, & Robergs, 2010.
2. Keyser, 2010.
3. Rogatzki, et al., 2015.

Breathing During Exercise.

If you’ve purchased the idea that your unconscious brain can learn to chronically hyperventilate while at rest, then it is a small stretch to understand that this also happens during exercise, but to a much larger degree than at rest as air hunger increases when engaged in very intense activities. As part of the normal metabolic processes of ATP production during mitochondrial respiration, the increased cellular activity of skeletal muscle during physical work creates increased levels of carbon dioxide (CO2), which gets pushed out to the blood. Pulmonary ventilation (breathing) exhausts CO2 from the blood. Remember from the last article that you need a certain level of CO2 in the blood for health and function so you don’t want to blow off too much CO2, but just enough.

The definition of hyperventilation is not what you might think—it is ventilating at rate higher than necessary for removal of excess CO2. That is, you are breathing too much—moving too much air—than is necessary to maintain adequate CO2 levels in the blood, and this can be far more pronounced during exercise than at rest. Hyperpnea is an increased ventilation rate that maintains healthy CO2 levels in the blood. Hyperpnea during exercise or physical activity should be expected due to the increase in metabolic CO2 production by the working muscle tissue. If you chronically, low-level hyperventilating at rest, then you are certainly hyperventilating during physical activity. And due to the Borh effect, just when your working muscles and brain need an increase in oxygen, the relative lack of CO2 is limiting its delivery. This drags your anaerobic threshold down—the metabolic point reached when the duration of physical activity will be limited unless the intensity is reduced. Moreover, overbreathing during exercise increases the biological cost of the training session, making you less resilient to life’s other stressors and/or reducing the frequency of your training sessions, resulting in lower overall performance. The reverse is also accurate: Reducing your ventilation rate during exercise leads to a lower biological cost and allows you to train more often.

The only way to reduce your ventilation during exercise is to practice. You have to practice controlling your breath during exercise and reducing the intensity of the exercise if breathing grows beyond your control. You should also practice some form of breathing at rest, with the goal of reducing your unconscious ventilation rate. This often overlooked activity that most of us take for granted will increase your physical performance to unexpected heights if properly harnessed. It’s one of those things that you need to experience to understand… I did, and many of my students did. Breath control and breathing practice is not something that is valued in the Western world, many but Eastern cultures have known about the benefits of controlling the breath for a very long time.

I personally ignored breath control of any kind for most of my life. I used to always run or train at a high intensity, with my mouth gaping open and sucking wind. First, I decided to close my mouth and breathe only through my nose. I had to slow down and train less intensely for a while (quite a while, actually), but then my ability to train harder returned—except now I was nasal breathing only. The effects were significant: I recovered much faster, I trained hard without excessive ventilation, I rarely felt muscles burning during training, and I slept much better.

Next, I took up a formal breathing practice at rest. My mood and mental attitude improved almost overnight. However, it took much longer for me to see the effects of my breathing practice to appear during activity, but when it did finally carry over, it had an incredible impact on my training. The key to understand is that this process is a slow one, but it will happen. Moving less air while you train allows you to work at very intense levels without the associated negative effects from anaerobic energy production. You’ll have to experience this for yourself before you understand. The dial on your CO2-ostat adjusts at a very slow pace, and only from concentrated consistent practice—but it is well worth the time investment.

Supporting Literature:

1. Streltsov, 1992. (http://www.iaaf-rdc.ru/eng/news/0027e.html)

Comment to citation: Although this scientist only published data on a limited number of subjects, it should be noted that the blood lactate levels dropped by 66% for the same training intensity in as little as six days of controlling breathing during activity—and this occurred in elite-level runners! There are plenty of other studies establishing a connection between lowered blood lactate levels during exercise and breath control.

The vector image is created by Vectorportal.com

Physical Training for Strength, Stress Management & Improved Health.

Physical training (PT) is one of the simplest and easiest additions (or changes) that you can make in your life. Physical inactivity is rampant in the western world, and its effects lay dormant for years before you might experience the symptoms of one or more of the 35 health conditions that it is associated with—including premature death. Physical training is not much more than moving with some purpose on a consistent basis. It doesn’t have to be formal, occur in a facility fashioned with furniture, nor does it need to be planned around the rest of your day. It does require some time and consistency, and your focused attention inward. To get the lasting benefits from physical training, you need to think about consistently nudging your physiological homeostasis toward the direction you wish. E.g., if you want dysfunction and disease, just continue to sit or lie down all day and night, minimize your walking and activity levels, and your physiological homeostasis will slowly but certainly move toward “sedentary”; and harboring a highly aerobic animal such as we humans in a sedentary lifestyle leads to undesirable adaptations. Just think about it in lay terms—biology, i.e., “life”, works on the rule of use it or lose it—if you sit around a lot, the ability to move, in any definition, fades. And, it is the underlying physiological changes that support reduced movement capacity, which also causes your health problems.

Alternatively, if you are seeking fitness and health, you do have to engage in those physical activities that nudge homeostasis in the other and opposite direction: Adaptations that provide good systemic function. And when I say nudge, I mean just that… at the time of this writing, we as a culture are still in the grips of the, “no pain, no gain” mantra, characterized by boot camps, high-intensity training programs, and the other types of group beatdowns that many fitness centers offer the public. These strategies are great ways to peak for a performance, if positioned on top of a long and general base-building program—you have to be able to absorb intense training in order to peak for a competition. However, when programs like these are utilized by folks with low levels of fitness, their body goes into a sort of shock mode, releasing a lot of body fat and stress hormones. While seemingly promising, this will only last for so long before the system shows signs of dysfunction. As opposed to nudging, I call this, sledgehammer training—taking a sledgehammer to your homeostasis is not a good idea. There is a better way.

Gently nudging your body into improved fitness and function is not sexy and no one needs to yell at you. You just simply have to put the work in, day after day, at an intensity that you can recover from. There are two major aspects of physical training: Strength and endurance. Plenty of gurus through the years have boxed their own categories of health & fitness, but they all simply boil down to one of the above two. Strength encompasses everything from how you posture and move, to how much of a load you can handle. For examples of strength work, you can think of everything from the postures of yoga, to the motor skill (re)training of physical therapy, to the heavy barbell deadlift, and, to the shorter sets of kettlebell snatches.

Endurance is, quite simply, everything that goes into allowing you to work at duration. The lines between the two can be blurred by performing extended sets of resistance, or, by carrying loads for distance.

The very best way to increase your endurance is to locomote; that is, to walk, jog, or run. The very best way to improve your strength is to load your structure—period. The former does not require any equipment or special clothing, it simply requires your time and attention. The latter is not what you think it is: To get the desired adaptations from strength training, you simply need to lift load—lift it off the ground; lift it over your head; or lift it an carry it around—just put your self in between the ground and a load with as much of your body as you can. It doesn’t require a lot of time, but you do need something to lift.

You don’t have to make time for formal physical training sessions in order to reap the benefits of movement—simply add habitual behaviors into your daily routine such as doing sets of push-ups throughout the day; walking instead of driving to work or for closer errands; carrying packages from the market instead of using a cart; using the stairs instead of the elevator; getting out from behind your desk every hour or so to walk laps around the building and/or lift some object with a challenging weight; or switching from a traditional desk to a standing desk. Every bit of movement helps you change from sedentary closer to active. Sure, you absolutely can prioritize and schedule physical training into more formal sessions during your day, but not doing so doesn’t mean you can’t be active at all.

Supporting Literature:

1. Booth, et al., 2017. (doi: 10.1152/physrev.00019.2016)
2. Kenney, Wilmore, & Costill, 2016. (ISBN-13: 978-1450477673)
3. The American College of Sports Medicine. (http://www.acsm.org)

Nutrition.

Nutrition is the simplest yet one of the more powerful lifestyle changes that you can make on your way to improved health, reduced stress, and greater physical performance. It is simple, but not at all easy. First, you have to reorient your view while contemplating nutritional intervention by peeling back technology, industry, and modern societal belief. The best indicator of what proper human nutrition is can be found in an evolutionary approach. That is to say, our past can be instructive to our present. To the best of our knowledge, we humans as a species have evolved over millions of years with certain environmental pressures that served to forge our current genetic makeup. Then, in a relative instant in time, our environment has radically changed due to industry and technology. The human genome is far slower to adapt to the novel environment it finds itself in. If you can understand this very simple but very important concept, the rest of this article will make some sense to you.

We are genetically mismatched to the lives we live, and this mismatch is causing problems for many individuals. The species, if given enough time, will adapt; but while that is occurring, individuals within the species will experience ill-health and disease—it is an expected part of the process. If you care about your health and fulfillment, you can’t wait for nature to adapt the human species. Many conditions that we classify as disease are not destinies needing a cure—they are the phenotypic expressions of the genetic mismatch. If you rematch gene to environment, the disease will abate. If you then again mismatch gene to environment, the disease will return. It’s not magic. Since, of the two, the environment is the variable that is in our power to change, it is lifestyle change and habits that can rematch gene to environment. If you eat in stride with your genetics, you will find health; if you eat against your genetics, you will find disease.

While I have your mind open, let me begin with the most radical idea in nutrition: Fasting. Simply stated, fasting is “not eating”. Depending upon what, and the size of your last feeding, several hours afterward, your physiology will switch from the fed state to the fasted state. The fed state is associated with relaxation, absorption, anabolism, energy transfer “in”; and the fasted state is associated with alertness, catabolism, energy transfer out. During the fasted state, the body’s cells do some spring-cleaning, a sort of reconstruction that is most healthful. There are far too many studies elucidating the beneficial effects of fasting on mammalian organisms to ignore this very powerful health tool. And if you think about it, we humans, and the animals that we keep with us are the only organisms on earth that constantly feed—it is societal, not natural.

Another well-studied dietary intervention is caloric restriction, one that also characterizes similar beneficial health effects. Fasting is not purposefully restricting energy intake; it is restricting feeding times only. There have been many authors and gurus who have boxed this no-cost intervention for sale to the public, and each have there own twist on fasting: One 24 hr fast per week; a 12-18 hr fast on most days; skipping one meal every day, etc. The simple truth is that it is better to eat less often than to eat more often, and how you do this can be completely individual. If you are not hungry, you do not need to eat. If you do get hungry, drink some water and wait 10 min to see if it was real hunger. Keeping your body in the fasted state most of the time will lead to the health benefits that you are seeking. It is not easy to begin using fasting as a tool, but that is only because you have been conditioned by society and your physiological systems are not as capable as they can be. Go slow at first.

So then, when it is time to eat, what is available to eat? The second perspective adjustment to correct is to adopt a chemist’s approach to food and metabolism. Once again, technology and industry have warped our perspective: The majority of nutritional recommendation can be found in proscription rather than prescription. We live in an age of food entertainment, and specifically engineered foodstuffs that cause addiction and repeat customers. The fact is that there is not as much of a variety of food as the local markets would have you believe. Food is: A plant or animal harvested and prepared so that it is close to its original life-form. The practice of industrially processing foods has fundamentally changed food into something that is simply, edible—a seemingly benign product that can wreak havoc on our health. Survival is not the same as thriving.

Sure there are some changes that man can make to food that doesn’t affect how it acts in your body, but the idea here is to first recognize what food is. Everywhere in the world, food is a plant or animal—period. Moreover, it is a plant or animal that was in good health when harvested. Vitamins and minerals? These are contained in healthy plants and animals, and transfer to you once digested. Human societies everywhere and throughout time, have subsisted on a range of dietary choices and all have thrived: Meat-only (note that the entire animal was used), omnivorous plant heavy, starch heavy, fish heavy, etc. We are highly adaptive creatures, but the theme is real food.

1. The sun provides energy that plants absorb into their being, along with micronourishment from the earth.
2. Some animals absorb those plants, energy, and micronourishment into their being.
3. Other animals absorb those animals, energy, and micronourishment into their being.
4. Yet some other animals, absorb both plants and animals, and their energy, and micronourishment into their being.

The natural food chain. Eat less often, and eat real food. So simple and so controversial, but it’s your health. The obvious antisocial aspects of these choices are not my concern.

Supporting Literature:

1. Feinman & Fine, 2004. (doi:10.1186/1475-2891-3-9)
2. Foster, et al., 2010. (doi: 10.7326/0003-4819-153-3-201008030-00005)
3. Harvie, et al., 2011. (doi: 10.1038/ijo.2010.171)
4. Joranby, Pineda, & Gold, 2005. (doi: 10.1080/10720160500203765)
5. Lo´pez-Lluch, et al., 2005. (doi: 1073/pnas.0510452103)
6. Mattson & Wan, 2005. (doi:10.1016/j.jnutbio.2004.12.007)
7. McInnes, 2013. (doi: 10.1186/1743-7075-10-63)
8. Nørrelund, et al., 2001. Diabetes. Jan. 50(1): 96-104
9. Speakman & Mitchell, 2011. (doi:10.1016/j.mam.2011.07.001)

Taking Control of Your Breath.

It should not be surprising that normal breathing is a foundational element of health, wellness, and stress reduction—it is the only thing that we do constantly from birth to death. You can live for several weeks/months without food and several days without water, but only several minutes without a breath. Yet, most of us allow our subconscious brain to control this task without giving it another thought. Every act you do and every thought you have can change the way you ventilate—in depth, rate, and mechanics. The subconscious/autonomic brain is conditioned by what it is repetitively exposed to.

We are aerobic creatures, that is, we produce energy for life with the assistance of oxygen (O2), and breathing assures a constant flow of O2 into the cells and tissues where it is needed. Without O2, you are soon in “oxygen debt”, creating energy in a hypoxic state through anaerobic means, which, if not corrected, will soon lead to unconsciousness and death. The O2 content of the earth’s atmosphere is about 21%, and this doesn’t change at altitude. Atmospheric pressure at sea level is 760 mm HG. Because the atmosphere contains several gases, each gas’ influence on the total pressure is called its partial pressure. The partial pressure of O2 (at sea level) is about 160 mm HG. Gases diffuse, or move from an area of high pressure to an area of low pressure, and the greater this difference, the greater the flow. In the human lung, an O2 partial pressure of 105 mm Hg creates a large difference with that of the incoming atmospheric air, which favors the transfer of a lot of O2 into the lung. Moreover, the partial pressure of O2 in the deoxygenated blood that passes over the lung is 40 mm Hg, so there is another large gradient between lung and the blood, ensuring a full supply of O2 to the blood with every breath. Just as water drains out of sink, O2 flows from the relatively high pressure in the air you breathe to your blood, and then out to your tissues and cells where it can be used. The main driver in this is simply the gradient difference.

Another gas of interest in the atmosphere is carbon dioxide (CO2). CO2 is thought to be nothing but a waste gas—in fact, a toxin in the human body. However there are many beneficial physiological effects that CO2 has on your physiology:

• increased oxygen delivery to tissues from the blood (Bohr effect)
• reduced blood pressure and heart rate
• balanced blood pH
• blood vessel and air passage dilation
• metabolic function improvements
• reduced nervous system excitability (reduces anxiety)
• improved brain function
• respiratory center sensitivity changes (easier breathing during activity)
• stabilized blood sugar
• improved immune function

As with most things in this world, the poison is in the dose. At 20% CO2 content, your health and function would surely fail, but surprisingly, at levels lower than 2.5%, you will also start to see dysfunction. CO2 is not the evil waste gas that it is made out to be. But, how does the CO2 content of lung and blood change?

In contrast to O2, the atmospheric content of CO2 is ~0.04%, a rather minuscule amount. The partial pressure of CO2 at sea level is 0.3 mm Hg. The partial pressure of CO2 in the human lung is 40 mm Hg. The partial pressure of deoxygenated blood flowing to the lung is 45 mm Hg. Most of the cells in your body create a lot of CO2 during normal metabolic function, and muscle tissue especially, creates a massive amount of it during increased activity. These partial pressure gradients favor the flow of CO2 from the blood into the lung, and then into the air in the lung, which you can then exhale, ridding the body of CO2. So, ventilating allows the body to intake O2 and exhaust CO2. However, the primary driver behind ventilation is the CO2 content of the blood. Although the brain has chemoreceptors that detect drops in the O2 content of the blood (these cause you to hyperventilate at altitude), it is the chemoreceptors that detect rising CO2 levels that are the most sensitive. Every medical and physiological textbook and scientific paper supports the idea that it is CO2 that drives breathing.

Professor Konstantin Buteyko was a respiratory physiologist who was assigned to work on the former-Russian cosmonaut program, researching optimal atmospheres for use in vehicles in space, aerospace and submarine. Also trained as a medical doctor, he noticed a relationship between hospitalized patients and their ventilation rate. The sicker the patient was, the more they hyperventilated. He theorized that the higher ventilation rate might be causing the condition instead of the other way around. So, he began having patients practice “breathing less”. There is a relationship between the partial pressure of CO2 in the lung, and your ventilation rate and depth—that is to say, the total amount of air that you move throughout the day is inversely related to the pressure of CO2 in your lung. Normal CO2 partial pressure in the lung is thought to be 40 mm Hg, which equates to about 4% of the total air. At this level of CO2, you will be moving about 6 liters of air per minute. Your ventilation rate will vary depending upon the depth of each breath, but medical research quotes about 12 breaths per minute on average. So, if the partial pressure of CO2 in the blood increases to some setpoint above 40 mm Hg (hypercapnia), then the respiratory center of your brain will increase your ventilation rate and/or the depth of each breath. In contrast, if the CO2 levels of the blood drop too far (hypocapnia), you will breathe less. This is how the brain maintains the correct level of CO2 in the blood, and this is a good thing because CO2 is the body’s main acid-base balancing tool, maintaining proper pH. But there is a problem in paradise and Professor Buteyko discovered it.

Due to the effects of the stress of life, your individual experiences, learned behaviors and responses, etc., you are continually urged to hyperventilate, which, actually has a definitive meaning: Ventilating more than is necessary to maintain normal CO2 levels. Hyperventilation, or “over-breathing”, can take the form of the obvious from the perspective of an onlooker, but it often presents in the form of low-level and chronic—meaning that you can only slightly over-breathe but on a continual basis. Hyperventilation in this form slightly reduces CO2 levels in the blood, and, over time (think in terms of years), the respiratory center of the brain changes its sensitivity to CO2 in the blood such that you will over-breathe, a negative spiraling effect: Over-breathing causes a drop in CO2 which causes a resetting (lowering) of the “CO2-ostat” in the brain, which results in over-breathing. You see, as the CO2-stat in the brain becomes more sensitive to CO2, it takes far less of an increase to produce an increase in ventilation. As a result, you ventilate more than you need to—while at rest, while active, and especially while stressed. Your body gets rid of the excess by relatively increasing ventilation (hyperpnea), but in the case of the aforementioned dysfunction, you are blowing off too much CO2.

There is a solution to this problem, and it is credited to Professor Buteyko: Take conscious control of your breathing—often. You have the power to change the CO2-ostat in the brain, but since there are no dials to manually change, practicing hypoventilation is the only way to get at and rectify this issue. In the same way that life’s experiences caused you to slightly hyperventilate which adjusted the knob on the CO2-stat down, you can consciously hypoventilate, readjusting the knob back up. This physiological change requires a lot of time and patience practicing, but it is highly effective and extremely rewarding. Our school of breathing practice has a long lineage of anecdotal successes to include Professor Buteyko’s own work. Changing the way you breathe has been shown to reduce the symptoms of over 200 different health conditions, not the least of which are high anxiety, depression, hostility/anger/irritability (propensity for violence), asthma & exercise induced asthma, high blood pressure, sleep apnea/snoring, headaches, low back/muscle pain, poor sleep, and fatigue.

Among the previously listed benefits of normal CO2 levels in the blood, the Bohr effect is an especially crucial one. Remember that it is the partial pressure gradient of a gas that causes it to flow… the body’s cells are using up O2 for normal metabolic function, creating a void of low pressure, so O2 should constantly flow through the downhill cascade of, “atmospheric air—lung tissue—bloodstream—cells”. However, there is an obstacle to this waterfall: 98%+ of O2 in the bloodstream is carried by hemoglobin, a protein contained in red blood cells. Hemoglobin that is carrying its full load of O2 is known as being “saturated”, and is called “oxyhemoglobin”. Although O2 will diffuse into and out of the blood as dictated by partial pressure gradients, hemoglobin and oxygen have something called an “affinity”, which is an additional force that is stronger than the pressure gradient. Like a beaver’s dam in the river, this affinity can be higher, restricting the flow of O2 against the gradient. Or, this affinity can be lower, permitting O2 to flow with the gradient. Though there are several mechanisms in the body that can lower the oxygen-hemoglobin affinity, CO2 is by far the strongest. Known as the Bohr effect, the presence of CO2 lowers the affinity and permits O2 flow, and the absence of CO2 strengthens the bond between hemoglobin and oxygen, effectively bottle-necking the flow of O2 from the blood out to the cells.

It should then be of little surprise that extremely aerobic animals such as humans present with disease and dysfunction when O2 flow is restricted. Moreover, there is always plenty of O2 around—it’s 21% of the air, it’s in your lungs, and it’s in your blood—sometimes, it just can’t get out to your tissues. Increasing the systemic CO2 level of the blood through breathing practice will finally allow the free-flow of O2 into your body’s cells where they are desperately needed!

Supporting Literature:

1. Austin, Brown, Watson, & Chakravorty, 2009. (doi.org/10.1164/ajrccm-conference. 2009.179.1_MeetingAbstracts.A3409)
2. (https://www.liverpool.ac.uk/~gdwill/hons/gul_lect.pdf)
3. Ferris, Engel, Stevens, & Webb, 1946. (doi: 10.1172/JCI101757)
4. Haldane, 1917. British Medical Journal 1(2928): 181-3
5. Hollidge-Horvat, et al., 1999. American Journal of Physiology 277 (4 Pt 1): E647-58.
6. Imtiyaz, & Simon, 2010. (doi: 10.1007/82_2010_74)
7. Loeschcke, 1982. Journal of Physiology (London). Nov. 332: 1-24
8. Peronnet, & Aguilaniu, 2006. (doi:10.1016/j.resp.2005.04.005)
9. Semenza, 2008. (doi: 10.1152/physiol.00045.2008)
10. Sinex, & Chapman, 2015. (doi.org/10.1016/j.jshs.2015.07.005)
11. Streltsov, 1992. (http://www.iaaf-rdc.ru/eng/news/0027e.html)
12. Tolner, et al., 2011. (doi: 10.1111/j.1528-1167.2010.02731.x)

Stress & the Stress Response.

Stress is an encroachment on your body’s life force. Your body does an absolute splendid job of maintaining the various systems that make up your life force within very narrow margins. The collection of your biological variables—the body’s temperature, blood sugar, bone mass, blood pressure, pH, skin pigment, adipose levels, heart rate, growth hormone levels, immune response, hydration level, oxygen content, etc.—are all kept within certain parameters, and this maintenance has been termed, “homeostasis”. In fact, this is what life is: The innate ability to withstand the natural forces of erosion. The environment within which you live is constantly trying to erode your biological systems. For example, if the ambient temperature grows cold, it will, if left unchecked, draw out your body’s heat. This encroachment is kept at bay as your body responds to this stressor, deploying several feedback loops to maintain your homeostatic internal temperature. Stress is a vital part of life. If there were no stress at all, you would be unable to deal with any changes in the environment and would effectively cease to be in this world that we know.

The body’s response to stress is elicited when system homeostasis is threatened—whether real or imagined. The intensity of the response is relative to the duration and intensity of the encroachment. The response is a cascade of neuroendocrine, neurotransmitters, cytokines, and growth factors that seek to mobilize energy and assist in restoring homeostasis. This action is mitigated through a negative feedback loop, which, similar to how your home’s thermostat operates, attempts to reverse a change in a variable. When the temperature of your home drops below the setting on the thermostat, sensors in the device send input to the furnace, switching it on to heat the air. When the air temperature then climbs above the setting, the device will send input to the furnace to switch off.

We may be able to say that environmental encroachments of very low intensity elicit little or no stress response and that the biological systems in place can correct the change. However, any system needs additional energy to work and one of the paramount functions of the stress response is to mobilize energy, so, perhaps the stress response is part and parcel of normal homeostatic function. As the stressor increases in intensity and/or duration, there is certainly a marked response of the stress system. For example, it is well known that a drop in blood sugar below normal levels—hypoglycemia—will elicit the stress response. However, under normal conditions, a slight drop in blood sugar “should” be corrected by the release a pancreatic hormone called glucagon, which acts on the liver, stimulating the release of glucose into the bloodstream. This is also one reason why fasting works well for some, not so well for others, and differently on the same individual at different times—the intensity of the associated stress response.

There is almost no function of the body that remains unaffected by the stress response. Arousal is heightened; sleep is reduced; metabolism, heart rate, and blood pressure are increased; growth and reproduction are halted; gastrointestinal function and digestion are inhibited; and the immune system and inflammatory response are enlisted. The body is primed to deal with the encroachment, and this is all part of a healthy functioning organism. However, as the duration of the encroachment lengthens, the stress response can change the function of the organism from normal and healthy to a pathological disease track. Hormesis is defined as a biological phenomenon that results in beneficial changes in an organism when exposed to low dose toxins for short time. This hormetic effect is none other than your body adapting to a stressor. Any stressor can be toxic if exposure is too intense and/or too long in duration. When the body adapts to a stressor in a beneficial way, with the associated stress response in retreat is called, “health”. The right amount of exercise has a hormetic effect; over-exercising leads to a diseased state.

Environmental encroachments—stress—affect us from everywhere, poor dietary choices, vehicular traffic, pollution, lack of exercise (or over-exercising), relationship friction, work obligations, etc; but the most intense of stressors in our modern society can affect us through our own mind. Psychological stress is an example of how the mind and brain (and body) are one. Something as seemingly benign as concern for an exam at school, or having an argument with your significant other, or socializing with new individuals can cause the same physiological response in the body as if fracturing a bone, or exposure to high heat. That is to say, something that doesn’t exist in reality—you create it in your mind—can cause a real event in the body. It is these psychological stressors that can wreak the most havoc on our system and degrade human health, however, the problem is compounded when psychological stress is coupled with physical stressors such as over-exercising, poor nutrition, poor oral hygiene, poor sleep hygiene, medical surgery, etc. So, in the context of worrying about your financial despair year in and year out, just a few cigarettes a day can finally result in disease.

Your ability to absorb stress, or your resilience to stress can be explained as a “biological bank account”. If you are constantly withdrawing from this account without depositing any currency, you will eventually show the signs and symptoms of system dysfunction and ultimately, disease. Because life is an ever-adapting force, a net withdrawal of your biological resilience can take years to present as dysfunction. Moreover, there are currently no accurate methods with which to measure the balance of this account. You can literally feel a strong physiological stress response to an encounter with a bear while out hiking on a trail, e.g., but there is no way to feel the low level of chronic stress that we all endure day to day. The eventual signs and symptoms are the only evidence of a drained account.

The symptoms of over-stress are largely individual; some folks will experience high anxiety and panic disorder, others will experience depression, others will accumulate body fat, some will avoid social situations, others still will suffer from frequent colds and illness, or migraine headaches. Attempting to seek relief from these symptoms, these individuals will seek medical care, that usually result in the use of pharmaceutical therapies, adding to the overall stress that the body must deal with. So, as one set of symptoms might abate, time might reveal a new set of symptoms, all with the same root cause—the encroachment(s).

If the body is over-stressed for a long while, it is devoting a lot of energy to merely keep you limping along. This energy must be diverted from another need: Exercise, organ function, immune capacity, etc. You might feel generally healthy; perhaps a little off, or maybe just tired… all the while there is vast concert being orchestrated underneath the surface that is trying to maintain homeostasis. The very base of human health, everything considered, is to manage your stress such that your biological account stays deep in the black. Stress management begins with the removal or reduction of as many of the controllable stressors in your life, e.g., improved nutritional choices, start exercising (or stop over-exercising), cease alcohol/tobacco use, etc. Stress management then continues with certain practices that enable you to change your attitude toward life to a more hormetic one. In other words, both physical and psychological stress needs to be attended to. Over time, your biological bank account will grow (you will heal) and your resilience to stress will once again allow you to live and fulfilled, functional and healthier life.

Supporting Literature:

1. Black, 2003. (doi:10.1016/S0889-1591(03)00048-5)
2. Charmandari, Tsigos, & Chrousos, 2005. (doi: 10.1146/annurev.physiol.67.040403.120816)
3. Chrousos, 2009. (doi:10.1038/nrendo.2009.106)
4. Kyrou & Tsigos, 2009. (doi: 10.1016/j.coph.2009.08.007)
5. McEwen, 2017. (doi: 10.1177/2470547017692328)