Monday, March 31, 2008

The Principles of Tribal Fitness: The Rhythm of the Hunt

31 March 2008, 20 April 2008

I am the archetypal civilized as opposed to tribal person. I am an aficionado of the highest achievements of human culture and civilization, from the great works of art to the accomplishments of music, architecture, drama and literature. While I am hardly the world's most cultured person (you may wish to visit the Juilliard School or the Banff School of Fine Arts to obtain a much greater dose of culture than I can personally convey to you), I am definitely at the civilized as opposed to the tribal end of the human cultural spectrum.

Be that as it may, I am going to spend the balance of this article advocating for a particular aspect of tribal human behaviour.


Because our survival - as individuals - depends upon mastering the principles of tribal fitness.

If we learn these principles, we stand to live well into the last decades of our lives (no matter how long or short the span that our own genetic program, habitual behaviours and environmental circumstances may actually allow us).

I have referred in an earlier entry to the groundbreaking text on fitness after 50, Younger Next Year. The phrase "rhythm of the hunt" came to me through an entry of Dr. Henry (Harry) Lodge on the Younger Next Year Website.

Dr. Lodge's entry is so well-written, I am tempted to quote it in full here, but that should not be necessary, as you can go directly to the source yourself.

What is Dr. Lodge suggesting?

In essence, humans have lived as tribal beings for over 99% of our two million years of evolution. This simple fact means that very little meaningful biological evolutionary development has occurred during our 7000 years at most of civilized life.

While culturally and psychologically, we may be very civilized beings, biologically, we are tribal beings, and that is simply a fact.

How then did we evolve - biologically - as tribal peoples?

In one term - as hunter-gatherers.

Again, no more than 1% of human evolution has been characterized by the three developmental stages subsequent to the hunter-gatherer lifestyle (horticultural/pastoral; chiefdom; civil society).

How do hunter-gatherers live?

Again, the brief answer is "from the gifts of the land." From a civilized perspective, that may seem a difficult lifestyle, but it was obviously good enough to tide our ancestors through 2 million years of evolutionary history.

For hunter/gatherers, sometimes the land gave, and sometimes it did not.

Going beyond Dr. Lodge, I would speculatively characterize the tribal (hunter/gatherer) lifestyle as involving three phases - linked to three types of activity.

Phase I is gathering the fruits of the land. The activity associated with gathering was probably many hours of walking, bending, stooping, digging, collecting, and intermittently resting, per day. While gathering implies a vegetarian component to our diet, this was not strictly a vegetarian activity, as many animal sources of nutrition are also susceptible to gathering, including the collection of shellfish, the gathering of eggs, and probably catching fish in many cases as well.

Phase I is characterized by a gentle sustained pace of exercise mostly equivalent to walking or jogging as an exercise form.

Phase II is hunting, and to the best of our knowledge, based on the study of contemporary hunter/gatherer societies, this was characteristically a group activity, and was accompanied by a number of active rituals, as well as by hunting forays to bring home high protein/high fat game for the tribal group.

Hunting involves not only vigorous running and effortful use of weapons and carrying of the kill, but also many complex and integrated bodily movements, such as twisting, striking, lifting, cutting, turning, altering direction and pace, etc.

Phase III - not mentioned by Dr. Lodge, but also obviously relevant to the tribal lifestyle, is fasting. In pastoral societies, such as that of the traditional Hunza, fasting was an essential element of the annual calendar, extending up to 6 weeks in late winter and early spring.

Periods of fasting are a time for conservation of energy. Notably, the scarcity of food has defined much about human biological development. Consider, for example, that our bodies' insistence upon the storage of fat is clearly an adaptation to the recurring shortage of food during our human and pre-human developmental history. When we diet, our bodies move into food scarcity mode, and increase the rate at which they store fat, frustrating the intentions of many would-be dieters.

Consider also that depressed mood is a survival mechanism in times of scarcity, as depressed individuals conserved energy, while active individuals risked wasting what little energy might have been stored in fat, with the result that they might not survive until the next season of plenitude.

By way of contrast, and here I am returning to the main point of Dr. Lodge's article, hunting is an optimistic activity. The hunter, through the expenditure of great effort, increases his chances of bringing home many meals, and thereby enhancing his chances of survival, as well as the likelihood of survival of his tribal group.

That is, biologically, the rhythm of the hunt offers some survival advantages over the rhythm of foraging.

To begin with, the slow, steady pace of the walking gatherer is a biological strategy for burning fat, but not carbohydrates. I suspect, though I'm reading between the lines in the evidence, that psychological depression (for the reasons I offered earlier) is also linked to the foraging versus the hunting way of life.

By way of contrast, the vigorous pace of the hunter entails the burning of the combined fuels of fat and carbohydrate, as well as to much more active use of the body as a whole - and this also appears to be linked to counterbalancing psychological processes.

Dr. Lodge states:

"Exercising hard enough to push yourself to the next level calls for a new fuel. You need more power than you get from fat alone, so your muscles start to burn glucose. This shift into high gear changes your metabolism, because harder exercise is the automatic signal to your body that you've started to hunt. Picture an animal when prey is in sight. His adrenaline surges, he becomes engaged and alert, his step has more bounce, he processes visual information more quickly, his reflexes sharpen, his pupils dilate. This is what happens when you turn on a whole serious of complex control mechanisms by exercising harder. When you reach this level, —starting to burn glucose—, your arms swing freely, you breathe more deeply, and your legs start to really work. You keep burning that low level of fat in the background, but all the extra fuel from this point on up is glucose.

"Your heart rate is the only way to know for sure which metabolism is at work and which signals you're sending. Your heart delivers more and more blood to your muscles the faster it pumps, and your muscles can extract more and more fat from that blood until you reach about 65 percent of your peak heart rate. That's the limit of your first gear, and only a heart monitor can help you determine which number that is for you. As soon as you push your body a little harder, you start burning glucose in addition to fat, and you need more oxygen to do this. That means bringing more blood to the muscles so your heart rate goes up. Any heart rate above 65 percent means you're burning glucose and that you've moved into a different metabolism. You've shifted into second gear and your body starts drawing on the glucose stored in your muscles, feeding it into your mitochondria to produce extra energy.

"Hard aerobics, working up a good sweat, is our favourite exercise rhythm because hunting brings out our youngest and best biology: strong, fast, energetic and optimistic all day long. But light aerobics builds the foundation for health better than anything else. That's why you should do light aerobic exercise a couple of days a week to build your base, and then go out and play on the hard-aerobic fields the other days."

I have quoted Dr. Lodge at length here, because there is little that I wanted to omit, and little that could be paraphrased more concisely.

The rhythm of the hunt, due to the efficient mitochondrial (aerobic) burning of carbohydrate fuel, engages a series of rejuvenating biological mechanisms that are not triggered by more moderate exercise.

In my earlier essay on the ideas of Younger Next Year, I made reference to the impacts of the cytokines 6 and 10 on human health and fitness. New research since that time has revealed that both cytokine 6 (more commonly referred to as IL6) and cytokine 10 (IL10) are anti-inflammatory cell-surface signalling proteins, and that the culprit involved in the cellular breakdown associated with arthritis, diabetes and cardiovascular disease is actually another very well-characterized cytokine known as TNF (I am simplifying perhaps too much in this section, for the sake of hoped-for clarity).

However, the fundamental idea of younger next year, and the first principle of tribal fitness, still stands.

When we do not exercise vigorously on at least an alternating daily basis, our bodies enter fasting mode.

Paradoxically, even when we are inactive, but flooding our bodies with calories, biologically, our bodies remain in fasting mode - because it is vigorous physical activity that signals our bodies that we are engaged in the gathering of food - not the inflow of calories!

The body of the well-fed inactive person believes it is starving. Not only does it begin to store fat at overtime rates, it also breaks down tissue to generate energy to burn - and this is the mechanism which triggers the onset of arthritis, diabetes and cardiovascular disease, as well as probably many other diseases, possibly including some types of cancer as well.

What about the biology of the gatherer?

It is much healthier than the biology of the inactive person, but still problematic, at least in our contemporary context, where our closest approximation to gathering is walking. That is, the original spectrum of "lifestyle" components of traditional gathering behaviour is typically eliminated in our contemporary forms of "moderate" exercise.

How so?

Quite simply, our bodies do not require the peak of fitness to walk about, staying active, but at no more than an easy to moderate pace. When we walk and take in calories, our bodies know that food is available - but easily so. Thus, muscle tissue gradually dies back, and the range of our bodies' capacity for exertion becomes restricted. This is not a serious problem for younger people, but potentially a very serious problem for persons over 50, who are already facing age-related declines in physical capacity.

That is, even regular but only mellow physical exercise permits us to come off our peak, and to function in a gradually narrower and narrower range.

Thus, of the three "phases" of tribal fitness, only one of the three enables us to live beyond age 50 with as full as possible a range of capacities - and that is phase II - the rhythm of the hunt.

As defined by Dr. Lodge, this means engaging our heart rate at 65% or more of maximum capacity, and engaging in strenuous (though not necessarily continuous) physical exertion (characterized in the text as "resistance training").

On the Younger Next Year website, Dr. Lodge and his partner Chris Crowley, are beginning to define more broadly what is really entailed by the rhythm of the hunt.

On the title page at this time is a reference to the new book, "Balance," by Scott McCredie. Mr. Crowley refers to Mr McCredie's conjecture that it may have been our human sense of balance - not our supposedly superior intelligence - that distinguished us from the Neanderthal.

Let me go beyond Crowley and Lodge here to add a few questions or conjectures of my own.

As I really understand the physical demands of the hunt in tribal societies (and let me hasten to add that I am a vegetarian, but my genetic code doesn't know it), there is much more demanded of our minds and bodies than our contemporary analogues of aerobic fitness, speedwork and weight training.

That is, our "linearly" structured contemporary exercise programs constitute no more than partial approximations of the actual rhythm of the hunt that we must replicate if we are interested in arresting the progress of the degenerative processes (and diseases) that are inherent to the aging process, as well as in maximizing our physical options through maintaining peak levels of endurance, strength, flexibility and agility.

I am beginning to think that combined aerobics and strength training, while beneficial - are simply not enough. I am not meaning to set an impossible challenge in terms of the time demands of fitness activities, but rather to be interested in thinking about how to combine activities that promote endurance, strength, balance, flexibility, agility and tolerance for variation in levels of effort.

That is - it is not "one or the other," but how to combine as many functions into a single activity as suits our personal interests, needs, constraints and lifestyle.

As a thought experiment, let me set out a few basic challenges, some of which I can presently pass, but some of which I cannot - and probably soon must be able to do!

Targeting particularly my readers over 50, can you.....

1. Complete a half marathon in any time at all?
2. Lift (pull up) your own body's weight on a horizontal bar?
3. Push up your own body's weight with your arms?
4. Easily exit a chair by exerting your abdominal muscles rather than by relying on the support and strength in your arms?
5. Comfortably assume and maintain a full squatting position (as one might witness in an Asian market)?
6. Both sit up and stand up from a lying-down (supine) position without using your arms to push or pull?
7. Maintain your balance while riding a bicycle or a horse over long distances?
8. Take off, put on, tie and untie your shoes from a standing position without support?
9. Run, turn and spin from position to position without losing your balance?
10. Engage in at least three demanding lifestyle fitness activities (for example, team sports, individual competitive sports, distance running, rock climbing, cycle touring, skiing, roller blading, distance swimming, active dancing, etc.)?
11. Run and keep your pace in deep snow or sand?
12. Balance on one leg (or better still - two arms)?

If you are 50, will you be able to do these activities when you are 70? Or if you are 60, to do them at 80, etc.?

What kind of fitness routine do you need to accomplish your own strategy for being "younger next year?"

There is much more I want to say, ask, and speculate about, but I will reserve these additional topics for a future article!

20 April 2008: It is important to clarify a point that is raised by my wife Susan in her recent blog entry, "Long Walks Are Good for Your Heart x2." She is exactly right that the transition from idleness to maximum exertion is a non-natural and high-risk behavioural pattern.

It would be more accurate to conclude not that the rhythm of the hunt is superior to the rhythm of foraging, but rather that it is a necessary and non-expendable complement to the pace of foraging. To rest and then to hunt, never engaging in foraging, seems an unlikely and unnatural life and exercise rhythm.

The rhythm of the hunt gains its validation against the backdrop of the rhythm of foraging. Both are necessary. Seeking to capture the pace of the hunter in our exercise program, without also mastering the pace of the gatherer, is almost certainly contraindicated by the innate biological program of our hunter-gatherer bodies!

Further, we would be wise to devote more time to mastering the rhythm of the gatherer prior to aspiring to the replication of the rhythm of the hunt. That is, let us first attain the rhythms of gathering and foraging before we seek to master the challenges of the far more demanding - and risky - rhythms of the hunt.

It is the gatherer who is ready to engage in the mysteries and rituals of the hunt, not the sedentary individual whose body is unaccustomed to regular and habitual movement and sustained aerobic exertion.

In the world of evolutionary (physical) fitness, we must certainly learn to walk before we can learn to run.


  1. This is a very intresting article. There are a lot of people (General Population) that don't realize how important physical activity and even light resistance training are. Women will assume, "oh no I don't want to lift weights." but little do they know muscle burns fat, not fat turns into muscle.

    Life styles have definitely changed over the years. Comparing my childhood to the chidhood of present children is totally different and a more sedentary lifestyle. It is said that children who had active lifestyles will have a stronger bone density reducing the risk of osteoperosis. Incorporating healthy lifestyles in this decade is getting harder and harder for people do. These sedentary lifestyle people have to reaslize that a healthy life style doesn't just come to you, you have to come to it.

    Over all Laurence, very good article. :)

  2. Thanks for your thoughts Megan.

    The point I really want to raise here is that being physically active involves comfort with and mastery of a spectrum of activity - a habit of hours of daily moderate activity, and the ability to stretch to peak levels of performance on a regular basis - several times per week.

    This involves a real shift from how most people live today!