Category Archives: Healthcare Industry

Paleo Fitness

My guilty pleasure is Quora, which I dip into if a question intrigues me. Sometimes I “archive” the more interesting topics here.

“If Paleo Fitness is supposed to be great, has anyone measured the fitness of Amazon Native to see how they perform? Specifically, what is their blood pressure, heart rate, VO Max, Mile Run time, Pull-ups, Push-ups, Deadlifts?“

Generally people in traditional societies have remarkable health markers, which is the basis for claiming that prior lifeways are more healthful. I think you would find, though, that in terms of actual, functional fitness that takes a person into a high-quality-of-life advanced age, the sheer number of pull-ups/pushups, the mile run time, or max power production, eg, in a deadlift, is simply irrelevant. Those things are not what constitute “great fitness.” A lot of the gym/fitness-test-based metrics for fitness are not actually about fitness itself but rather run the gamut from impressive speed to impressive strength to cool tricks you can do with the human body. For the first 3, which are actual health markers, some of the groups who have been studied extensively (eg, Hadza people) are absolutely in better shape and retain their good markers later in life than most Westerners – yes, even for VO2 max.

As I understand it, Paleo Fitness, the book, is not actually about paleolithic or nomadic/seminomadic lifeways per se – it’s about trying to bring our overall activity level up to something consistent with evolutionary pressures. It emphasizes spontaneity and “play”-style movements, and Edwards also emphasizes how aversive and frankly hostile a lot of the general claims about fitness/exercise are (“sweat is your fat crying,” “no pain, no gain”). He seems like a wonderful person, and his recommendations look like fun! But it’s only “Paleo” in a snappy, eye-catching sense: Edwards is coming from the basic idea of the mismatch between human body evolution and the modern, “developed”-society patterns of sitting on your butt all day, sure, but he is offering correctives to that mainly from the play angle rather than “how can I do heavy work.” (Indeed, one of his catch phrases is “Working out is not working out” precisely because structured exercise like performance-oriented running or lifting programs are enjoyable to very few people, and – starting every January – abandoned by people in droves.)

10,000 years ago, food insecurity was possibly the greatest threat to human groups, and food acquisition required a fair bit of movement, so you wanted to be up to it but you also didn’t want to waste calories. Ancient people were kind of on the “see food” diet – they didn’t survive by passing up calories, or by expending more than they took in just to test themselves. Part of what any fitness program is about includes calorie deficit, simply because our built environments are awash in calories in a way that our brains haven’t caught up with. So modern fitness programs are, in many ways, from a completely different world to that inhabited by people still living by ancient lifeways. If you showed any fitness book to people living hunter-gatherer lifestyles, they’d probably wonder why anyone needed it. If you told people that it was valuable to have a very fast mile time or a huge deadlift, they’d probably think you were nuts, even if they might well also think it would be cool to see someone demonstrate that. Ironically, one of the most impressive “paleo” activities out there, and one that no fitness program claiming “Paleo” roots ever emphasizes, is simply being able to follow a large animal at a walking pace until it collapses from exhaustion. That combination of terrain familiarity, strategy, orienteering, and sheer endurance is a form of fitness Paleolithic people could actually use.

Links:
My answer at Quora
Exercised: Why Something We Never Evolved to Do is Healthy and Rewarding, by Daniel E. Lieberman
Paleo Fitness, by Darryl Edwards with Brett Stewart and Jason Warner

How much exercise is enough?

My guilty pleasure is Quora, which I dip into if a question intrigues me. Sometimes I “archive” the more interesting topics here.

“Is walking for 45 minutes a day enough to not have a sedentary lifestyle if you sit behind a desk for 7 hours a day?“

Medically, we don’t really have a clear, single definition of “sedentary lifestyle,” beyond knowing that a society in which a large number of people work in a sitting position means people do need to make purposeful effort to ensure they have adequate movement during the day. Most studies and government-issued guidelines around sedentary behavior cite health risks as being more common above a threshold of around … 7 hours a day (perhaps the reason you mention that number), although some suggest it is lower.

There are, of course, definitions of sedentary behaviors, and there are studies of health outcomes with respect to different kinds of sedentary behaviors. For example, there is research showing that hours of television watching is associated with poorer health outcomes, but the evidence for sitting to do other activities “behind a desk” (more cognitively demanding, such as work or using a computer for something other than just watching video) is not as negative, so we can’t even necessarily think of the mere fact as sitting across time as defining a “sedentary lifestyle.”

In the US, the guideline for adequate weekly activity to improve health outcomes works out to about 25 minutes a day of walking – less for vigorous exercise like running. The data we do have about exercise indicates that health benefits continue to accrue as exercise level increases, to a point that far exceeds 45 minutes a day. For people who like evolutionary explanations, investigators who work with societies that still practice hunter/gatherer lifestyles tend to find they are active on the order of 3 to 5 hours a day, of which over an hour is moderate to vigorous physical activity, so about triple the recommended level, and almost double 45 minutes a day. Very importantly, their activity levels don’t drop off with age as much as the activity levels of people living in westernized societies; they remain quite active throughout the life course.

This still leaves us with the question of what we should aim for. Studies that look for associations with better outcomes at different levels of steps per day keep finding more up to about 16,000. At that level, it’s hard to analyze effectively because there are not enough people who do it, or not enough people with different characteristics who do it. For example, it is possible that people who routinely walk more than 2 hours a day are different in many ways from people who walk 5,000 to 10,000 steps a day, and so it would not be possible to compare the two groups solely on the basis of walking volume.

From what we do know, 45 minutes a day, assuming that covers at least 5000 steps, will certainly be helpful, and it greatly exceeds the US activity guidelines (which are more of a starting point than a limit). More is almost always better. From a healthy aging perspective, being active consistently and daily – and including some strength training – is a key to a higher quality of life, and greater independence, for longer.

My answer on Quora

The Side Effects Tell You It’s Working

If you go by American Psychiatric Association diagnosis standards, half of us meet the criteria for mental illness at some point in our lives. And sometimes it seems like all of us are on antidepressants. But do we need to be?

It is important that clinical trials, particularly those dealing with subjective conditions like depression, remain double-blind, with neither patients nor doctors knowing whether or not they are getting a placebo. That prevents both patients and doctors from imagining improvements that are not there, something that is more likely if they believe the agent being administered is an active drug instead of a placebo. Faced with his findings that nearly any pill with side effects was slightly more effective in treating depression than an inert placebo, Kirsch speculated that the presence of side effects in individuals receiving drugs enabled them to guess correctly that they were getting active treatment – and this was borne out by interviews with patients and doctors – which made them more likely to report improvement. He suggests that the reason antidepressants appear to work better in relieving severe depression than in less severe cases is that patients with severe symptoms are likely to be on higher doses and therefore experience more side effects.

—Marcia Angell, “The Epidemic of Mental Illness: Why?” [emphasis mine]