Active Grandparenting, Costly Repair
From the book EXERCISED: Why Something We Never Evolved to Do Is Healthy and Rewarding by Daniel E. Lieberman, to be published on January 5, 2021, by Pantheon Books, an imprint of The Knopf Doubleday Publishing Group, a division of Penguin Random House LLC. Copyright © 2020 by Daniel E. Lieberman.
Editors’ note: Love it or hate it, exercise is a vital component of health. Harvard Magazine has explored exercise from its epidemiological impacts and its basic biology at the level of mitochondria, to its potent anti-inflammatory effects. Several other articles have covered the research of Lerner professor of biological sciences Daniel E. Lieberman, who brings an evolutionary and anthropological perspective to unpacking the paradox that humans are adapted to run (“Head to Toe,” January-February 2011, page 25), but have evolved to conserve energy, not expend it (“Born to Rest,” September-October 2016, page 9). In this feature, excerpted and adapted from chapter 10 of his new book Exercised: Why Something We Never Evolved to Do Is Healthy and Rewarding (Pantheon Books), he integrates diverse lines of evidence to explain what happens to the body during physical activity—and why it is healthy.
Everyone wants to live long, but no one wants to get old. So for centuries people have sought ways to slow aging and defer death. Not long ago, quacks would have tried to lure you to consume tobacco, mercury, or ground-up dog’s testicles to postpone your eternal rest; today’s peddlers of immortality hawk human growth hormone, melatonin, testosterone, mega-doses of vitamins, or alkaline food. For millennia, however, the most sensible advice has always included exercise. Just about everyone knows what countless studies confirm: regular physical activity slows the aging process and helps prolong life. I doubt anyone was astounded when Hippocrates wrote 2,500 years ago that “Eating alone will not make a man well; he must also take exercise.”
