Exercise already! Regular readers are no doubt sick and tired of hearing about it, but until such time as sensibly directed funding and hard work in the life sciences produce medical technologies that can do better for humans, regular exercise remains one of the two best tools we have to slow our inexorable slide into frailty and disease. It allows us to somewhat shift our life expectancy, and greatly reduce the risk of suffering all of the common chronic conditions of aging.
For those in the middle of life, looking at an ever-uncertain future of technological development, a few years added or subtracted might make all the difference in the world. When it comes down to the wire, will you make far enough to benefit from the first commercial rejuvenation biotechnologies, or will you fall short and be forced to take the second worst end of life option, with an unknown chance of eventual restoration? These are weighty questions, and burying your head in the sand is essentially the same as picking the poorest answer for yourself.
An article on this general theme from the popular press, which goes on to point out a range of data on exercise and specific age-related conditions:
"There's compelling data that older individuals participating in exercise programs show dramatic improvement in function and abilities," says Cedric Bryant, chief science officer for the American Council on Exercise in San Diego. In fact, experts suggest that many ills once attributed to normal aging are now being viewed as a result of chronic inactivity.
Despite this promising message, fewer than 5 percent of seniors follow the recommended guidelines for physical fitness (30 minutes of moderately intense exercise on most days). "Levels of activity in people 65 and older haven't budged in decades," says Miriam Nelson, director of the John Hancock Research Center on Physical Activity, Nutrition, and Obesity Prevention at Tufts University in Medford, Mass.
Even if they've never exercised, the middle-aged and older can still benefit by beginning now. Experts say sedentary people will actually fare better in percentage gains relative to active people, since they're starting from zero. "It doesn't matter how old you are," says Colin Milner, founder and CEO of the International Council on Active Aging in Vancouver, British Columbia. "It's never too late to start exercising."
As a specific example of the sort of low-level mechanisms by which exercise impacts long-term health, you might look at this paper:
A decline in mitochondrial biogenesis and mitochondrial protein quality control in skeletal muscle is a common finding in aging, but exercise training has been suggested as a possible cure. In this report, we tested the hypothesis that moderate intensity exercise training could prevent the age-associated deterioration in mitochondrial biogenesis in the gastrocnemius muscle of Wistar rats.
Exercise training, consisting of treadmill running at 60% of the initial VO2max, reversed or attenuated significant age-associated (detrimental) declines in mitochondrial mass ... Exercise training also decreased the gap between young and old animals in other measured parameters ... We conclude that exercise training can help minimize detrimental skeletal muscle aging deficits by improving mitochondrial protein quality control and biogenesis.
Mitochondrial damage - and thus processes such as autophagy that attempt to reduce levels of mitochondrial damage - seems to be very important in aging. Given that many mechanisms associated with longevity are seen to influence autophagy, it should not be surprising to find exercise on that list.