We may be getting exercise all wrong, according to a Harvard professor

We have to completely rethink the concept of exercise, Harvard biologist Daniel Lieberman said.

Speaking to the Harvard Gazette, Lieberman said we need to realize that humans were never meant to exercise for leisure — and that’s fundamentally wrong.

“We live in a world where everyone knows that exercise is good for you, and yet the vast majority of people have a hard time doing it,” Lieberman said “For me, it’s clear we’re asking people to choose to do something that’s inherently abnormal in the sense that we evolved not to do it.”

Speaking from the standpoint of an evolutionary biologist, he said that our modern obsession with fitness makes no sense.

“Humans evolved to move. We evolved to be physically active,” Lieberman said. “But exercise is a special kind of physical activity. It’s voluntary physical activity for the sake of health and fitness. Until recently, nobody did that. In fact, it would be a kind of a crazy thing to do, because if you’re a very active hunter-gatherer, for example, or a subsistence farmer, it wouldn’t make sense to spend any extra energy going for a needless five-mile jog in the morning.”

That may have been true for the Cro-Magnons. However, as long as 5,000 years ago, exercise was beginning to become a hallmark of vanity in addition to a facet of physical health. In ancient Greece, gymnastics was often as popular as music or art, and running was an enormous part of their routine. This kind of exercise for fun petered out in the Middle Ages as poverty, famine, and disease were all-consuming.

But gymnastics reemerged in popularity in the 1700s, where its permutations and variations have remained as prominent methods of staying fit (namely weightlifting and running). Periods of war or hardship can cause exercise to fall out of fashion, but when societies urbanize and become wealthy, it becomes a hobby rather than a necessity.

“Now, we judge people as lazy if they don’t exercise,” Lieberman said, adding that people who don’t work out aren’t lazy. “They’re just being normal.”

What should exercise actually be?

The idea that our ancestors didn’t exercise doesn’t mean that we shouldn’t be trying to stay healthy. Lieberman simply argued that we must rethink the way we exercise and why we feel motivated to do so.

The first thing that Lieberman recommended is to treat yourself kindly and not be mad at yourself for not wanting to exercise. It’s not ingrained in our DNA to want to exercise in this way, he argues so these instincts are legitimate.

“Learn to recognize these instincts so you can overcome them,” he said. “When I get up in the morning to go running … my brain often tells me all kinds of reasons why I should put it off. My point here is to be compassionate about yourself and understand that those little voices in your head are normal.”

Next, Lieberman said, it’s important to remember that, as humans, we were primarily active for only two reasons: when it was necessary and when it was socially rewarding.

“Most of our ancestors went out to hunt or gather every day because they would otherwise starve,” he said. “The other times they were physically active was for fun pursuits like dancing or playing games and sports. If we want to help ourselves exercise, we need to have that same mindset. Make it fun but also make it necessary.”

Lieberman’s final piece of advice was that you shouldn’t be worried about how much time or how much exercise you need, just that you’re doing something, no matter how small.

“There is a myth that we evolved to be perpetually active, run marathons, and be so bulked up we can lift giant rocks with ease,” he said. “The truth is far from that. Our ancestors were reasonably but not excessively active and strong.”

So that should be one’s goal: reasonable but not excessive.

“Dose response curves show that just 150 minutes of exercise a week — only 21 minutes a day — lowers mortality rates by about 50 percent,” Lieberman said. “Knowing that, I think, can help people feel better about doing just a little exercise instead of none.”

The takeaway

There’s a pattern of humans engaging in more elective forms of physical activity when the going is good and struggling to keep up physical activity that isn’t directly tied to survival when the going is bad. But in the same way that we have slightly larger brains than our ancestors, perhaps our bodies have evolved in similar ways.

It isn’t some secret code in your DNA telling you that you don’t want to work out — maybe it’s just you. If you don’t want to work out, just accept the fact that you may not want to exercise that day for whatever emotional, physical, or environmental reason.