"Why is regular physical activity the best way to delay senescence and extend life?"
At HAT, facilitating inter-generational connections is at the heart of what we do. Seniors post jobs that appeal to high school and college students. They meet organically across generations. Help also works the other way: busy parents post jobs that retirees and empty nesters fill: driving kids to after-school activities, getting the children ready for school in the morning, cooking, tutoring, or fixing things around the house. Older neighbors are helping young families in their neighborhood and making inter-generational connections where the helper and the helped are reversed.
It turns out this kind of help is physically good for you.
"According to this theory, hard-working and helpful grand-parents who looked out for others and who were blessed with genes that favored a long life had more children and grand-children, thus passing on those genes. Over time, humans were evidently selected to live longer to be generous, useful grandparents. One version of this idea is known as the Grandmother Hypothesis in recognition of the evidence that grandmothers play especially important roles."
If you are retired and don't have grand-kids nearby -or at all-, HelpAroundTown can connect you with a nearby family that would love your help
The article goes on to make more interesting points. • Differentiating between aging and the deterioration due to aging, called senescence "Aging is inexorable, but senescence, the deterioration of function associated with advancing years, correlates much less strongly with age." • Arguing that physical activity slows down senescence "Humans were meant to move. (...) "Physical activity prevents or ameliorates bad things that accelerate senescence."
• Arguing that effort is the only way to get the benefits of activity The author's Costly Repair Hypothesis argues that the body only spends the resources necessary to repair damages when forced to do so by a trigger such as exercise. To tap into our bodies' ability to repair muscle and bone damage, clean up oxidants, etc., we must first generate the stress of exercise. "The modest physiological stresses caused by exercise trigger a reparative response yielding a general benefit. a phenomenon sometimes known as hormesis."
The article cites an interesting study of 5 healthy 20 year-olds who were asked to spend three weeks in bed. Those three weeks made their blood pressure, cholesterol, fat levels, muscle mass, etc. on par with 40 year olds. The youth then followed 8 weeks of exercise, reversing the deterioration and even improving some health data. 30 years later, these 5 Americans had gained 50 pounds, had high blood pressure and weaker hearts. They followed a six month program of walking, jogging and cycling. "After six months of moderate exercise, the average [50 year old] volunteer's blood pressure, resting heart rate, and cardiac output, returned to his 20-year-old level."
• Arguing that active grand-parents during the course of human evolution naturally engaged in plenty of physical activity
"Almost no one in the Stone Age, least of all grand-parents, managed to avoid hours of walking, running, digging, climbing and other manual labors. Hunter-gatherers of all ages would have stimulated their bodies' natural reparative mechanisms nearly every day in response to the demands posed by their way of life."
If you take antioxidant pills, the end of the article mentions a study that found taking antioxidant pills can be more harmful than helpful.