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.
There’s a symptom review, there’s a travel review, and there’s an exposure review. And if the answer to any of those questions is yes, then you’re asked to not come in. And so far people have been compliant and have left. So that is a good thing.
“These results are exciting, as they suggest that people may potentially prevent brain shrinking and the effects of aging on the brain simply by becoming more active,” said study author Yian Gu, Ph.D., of Columbia University in New York and a member of the American Academy of Neurology.
Across the 6 studies of 8699 participants, mean age ranged between 70 and 74 years and mean gait speed ranged between 1.05 and 1.26 m/s. Incident dementia ranged from 5 to 21 per 1000 person-years. Compared with usual agers, participants with only memory decline had 2.2 to 4.6 times higher risk for developing dementia… 
We observed that increased adherence to the MedDiet modulates specific components of the gut microbiota that were associated with a reduction in risk of frailty, improved cognitive function and reduced inflammatory status.
Challenging widely held assumptions about the diminishing abilities of an ageing brain, leading neuroscientist Daniel Levitin argues that we should view getting older as a beneficial experience rather than a form of cognitive entropy. Persuasively argued and consistently surprising, The Changing Mind will alter your perception of the relationship between age and intellect.
Boomers Daily 