In Exercised (Pantheon, Jan. 2021), Harvard paleoanthropologist Daniel E. Lieberman takes the modern fitness industry to the mat. The book is “a natural history of physical activity, and an attempt to demythologize and debunk all the ways in which people misunderstand physical activity,” Lieberman says. “We’ve commercialized it. We’ve industrialized it. We’ve commodified it. We’ve medicalized it. But really it’s just normal behavior.” PW’s review called the book an “illuminating and frequently humorous work.” Here, the author addresses its central question: why is something humans never evolved to do so healthy and rewarding?
What prompted your scientific interest in exercise?
I went to a medical conference at the Ironman Championships in Hawaii, [and watched] amazing feats of endurance. Two weeks later, I was doing fieldwork in Northern Mexico, with the Tarahumara [people]. They’re famous for long-distance running, and I was expecting to see people running all over the place barefoot, but I didn’t. I kept asking people about how they train. They all were confused by this question; my translator was trying to figure out how to explain what I meant by training. Finally one elderly guy looked at me and said, “Why would anybody run if they didn’t have to?” It’s such a simple statement, but it was one of those moments. I realized that we didn’t evolve to exercise, and I started thinking about how exercise is a very modern, abnormal kind of behavior.
What in your research surprised you?
Each chapter of the book is framed around a myth, and many of those are myths that I myself had. Hunter-gatherers, these icons of physical activity, they sit as much as we do. We’re told that sitting is the new smoking, but actually it’s an ancient behavior that everybody does. We color it in this virtue-laden, biased way without looking more broadly at how animals and humans work. That’s part of the fun of writing a book: it forces you to evaluate your own misconceptions.
Has the current public health crisis colored your thinking about the book?
One of the tragedies of this epidemic is how it’s exposed the inequalities in health and in opportunities to be healthy. For most of human history, it was only the privileged who could avoid being physically active and now it’s completely flipped. There’s a section in the book on depression and anxiety and stress. Physical activity helps your immune system and helps prevent a lot of the comorbidities that make people more susceptible to this disease. It’s also the most profound and effective way to help treat stress and depression and anxiety. We cannot solve these problems by thinking about exercise the way we do. We need to take a more broad, anthropological, evolutionary perspective.
What do you hope that the reader takes away?
I wrote the book for people who are feeling ambivalent, confused, and bullied about exercise. About 80% of Americans don’t exercise in their leisure time, but it’s not that they don’t know that exercise is good for them, and it’s not that they don’t want to. They’re made to feel ashamed, but they’re actually being totally normal. We should stop blaming people for not exercising. It’s a very modern, strange behavior, which we have to choose to do, and it’s not easy.