Longer lives are linked to physical activity, confirmed research released today, based on the assumption that humans evolved to remain active as they age.
Exercise at older ages diverts energy away from processes that can compromise health and towards the body’s mechanisms that extend it, said a team of evolutionary biologists and biomedical researchers at Harvard University in the US.
Such activity protects against chronic diseases such as cardiovascular disease, type 2 diabetes and even some cancers, the authors say in a paper published in the US National Academy of Sciences’ weekly journal PNSA.
“It’s a widespread idea in Western societies that as we age, it’s normal to slow down, do less and retire,” explained Harvard evolutionary biologist Daniel E. Lieberman, lead author.
Our message is the reverse: as we age, it becomes even more important to stay physically active, he said.
The experts said the study is the first detailed evolutionary explanation for why lack of physical activity as we age increases the risk of disease and reduces longevity.
They used chimpanzees as a starting point and pointed out that chimpanzees, aged 35-40 in the wild and rarely surviving past menopause, are considerably less active than most men.
Such a situation is especially jarring when compared to contemporary hunter-gatherers, who average about 135 minutes a day of moderate to vigorous physical activity, the paper noted.
It noted that that level of movement, about six to 10 times more than the average American, is a key reason why hunter-gatherers who survive childhood average about seven decades.
That’s about 20 years beyond the age at which humans stop having children, and they also enjoy a longer “lifespan,” defined as years of life spent in good health, the paper noted.