HARVARD MAGAZINE (SEPT – OCT 2020): From the book EXERCISED: Why Something We Never Evolved to Do Is Healthy and Rewarding by Daniel E. Lieberman, to be published on September 8, 2020 by Pantheon Books:
‘….many of the mechanisms that slow aging and extend life are turned on by physical activity, especially as we get older. Human health and longevity are thus extended both by and for physical activity.’
The graph breaks total energy expenditure (TEE) into two parts: active energy expenditure, and resting metabolism. Resting metabolism remains elevated for hours even after exercise ceases, burning additional calories in a phase known as excess post-exercise oxygen consumption (EPOC).
Exercise is like scrubbing the kitchen floor so well after a spill that the whole floor ends up being cleaner. The modest stresses caused by exercise trigger a reparative response yielding a general benefit.
In order to elucidate the links between exercise and aging, I propose a corollary to the Grandmother Hypothesis, which I call the Active Grandparent Hypothesis. According to this idea, human longevity was not only selected for but was also made possible by having to work hard during old age to help as many children, grandchildren, and other younger relatives as possible survive and thrive. That is, while there may have been selection for genes (as yet unidentified) that help humans live past the age of 50, there was also selection for genes that repair and maintain our bodies when we are physically active.
Daniel E. Lieberman is a paleoanthropologist at Harvard University, where he is the Edwin M Lerner II Professor of Biological Sciences, and Professor in the Department of Human Evolutionary Biology. He is best known for his research on the evolution of the human head and the evolution of the human body.
The book follows the journey of a writer in search of wisdom, as he encounters twelve distinguished American men over 80 — including Paul Volcker, the former head of the Federal Reserve, and Denton Cooley, the world’s most famous heart surgeon. In these and other intimate conversations, the book explores and honors the particular way that each man faces four challenges of living a good old age: Am I still a man? Do I still matter? What is the meaning of my life? Am I loved? 
Noted Harvard-trained geriatrician Louise Aronson uses stories from her quarter century of caring for patients and draws from history, science, literature, popular culture, and her own life to weave a vision of old age that’s neither nightmare nor utopian fantasy—a vision full of joy, wonder, frustration, outrage, and hope about aging, medicine, and life itself.
Lifespan, by geneticist David Sinclair and journalist Matthew LaPlante, provides a vision of a not-too-distant future in which living beyond 120 will be commonplace. For Sinclair and LaPlante, the answer lies in understanding and leveraging why we age…
Boomers Daily 