Today, when we get sick in our 50s or 60s from diabetes or heart disease or whatever ails us, we go to the doctor, but that didn’t exist until recently. Prior to medicine, health span equaled life span.
The first hypothesis is that in humans, physical activity evolved to help extend health span. I started thinking about how hunter-gatherers don’t retire, they stay really physically active.ĭo we know why physical activity keeps us healthy longer? We evolve to live after we stop reproducing. That seems really interesting because humans are unusual in that we evolve to be grandparents. Studies by Ralph Paffenbarger shows that as we get older, physical activity actually becomes more, not less, important as we age. This interview has been condensed and edited for clarity. life span, why stress from exercise is good for us, and which animals are couch potatoes. Lieberman spoke with STAT from Copenhagen, where he is pursuing further research, about health span vs. In a new review published Monday in PNAS, Lieberman and his Harvard co-authors grapple with the “active grandparent hypothesis,” using biomedical research and evolutionary studies to explain how humans evolved to need physical activity, particularly in and after middle age, to increase life span and reduce the risk of disease. Lieberman’s research interests range wider than running, spanning physical activity across the evolutionary history of what moves humans, in the industrialized world and in traditional hunter-gatherer societies.
His name has been connected to running and human evolution ever since his seminal Nature study “Endurance running and the evolution of Homo” appeared in 2004, and he’s been linked to barefoot running in particular after a 2010 study, also in Nature, explored the impact of modern padded running shoes on our strides. Exclusive analysis of biotech, pharma, and the life sciences Learn MoreĮvolutionary biologist Daniel Lieberman takes the long view of physical activity.