Exercise and Anti-Aging: A Surprising Finding
According to a study called “Physical activity and telomere length in U.S. men and women”, exercise really does slow cellular aging.
Researchers at Brigham Young University studied the DNA of nearly 6,000 adults. They found that the telomeres, the end caps on chromosomes that shorten with age, were longer in people who were active compared to those who were sedentary. This correlated to a 9-year difference in cellular aging between those who were active versus those who were inactive.
The amount of exercise made a dramatic difference. Telomere base pair differences were far greater in adults with Sedentary, Low, and Moderate activity than adults with a high activity level.
Adults with high levels of physical activity were estimated to have a biologic aging advantage of 9 years when compared to sedentary adults.
The difference in cell aging between those with low and moderate activity was also significant. Those who exercised at a high level had an 8.8 year biological advantage. They had a 7.1 year advantage over those who did moderate amounts of exercise. This suggests that people who get low or moderate levels of exercise are aging much more rapidly than those who are able to maintain a high level.
Overall, any level of physical activity was associated with an improvement in telomere length in both men and women in the United States. People with high levels of physical activity have longer telomeres, associated with years of reduced cellular aging compared to their more sedentary counterparts.
A few thoughts on this study.
First – I’m a fan of exercise. I find studies like this motivating because they remind me to keep doing it.
Any exercise appears to be better than none. But this study also clarifies that if you really push yourself, you will get significantly more anti-aging benefits.
One question that comes up around this topic is whether telomeres are a marker of aging, or a a key driver or aging. They were once thought to be a driver, but most researchers view them more as a marker these days.
Still, they’re an important marker because they can allow us to gauge what’s going on in our bodies. The aging process is so gradual, it can invisible to us sometimes. Studies like this make it visible, and allow us to see which interventions may be making the most difference.
Things that can lengthen telomeres, apart from exercise, include the traditional Chinese herbs astragalus and ashwagandha. Nutrients found in green and white tea are also associated with longer telomeres. Factors such as obesity, eating a low nutrient diet, smoking, and having type 2 diabetes, have been found to shrink telomeres; so getting rid of excess belly fat, quitting smoking, and reducing our consumption of low quality carbs can also keep our telomeres from shrinking.
A 2021 study called “Effects of exercise on cellular and tissue aging” makes an interesting point about exercise versus caloric restriction. In one sense caloric restriction is the gold standard in terms of anti-aging interventions. It’s been shown to prolong lifespan in dozens of species, including our fellow mammals. But it can have some drawbacks, including leaving the animals with lower sex drive, the onset of cardovascular problems, a tendency toward becoming too lean, difficulty adapting to changes in temperature, and depressed immune systems.
According to the study, quote,
When compared with other interventions directed at slowing aging, such as caloric restriction, some studies have shown that in mice, exercise lacks the adverse outcomes that were observed with time restricted feeding, and should therefore be a first line choice as an anti-aging strategy.”
In other words, exercising has greater benefits and fewer risks, broadly speaking, than caloric restriction, whether the caloric restriction is from ongoing dietary restrictions or from intermittent fasting
Living beyond 120
One last thought is that there’s no evidence that I’m aware of that exercise will help us live longer than the presumed maximum of around 120 years. So in that sense it might be less effective then caloric restriction, which has pushed a lot of species way past their previous known lifespan. But of course, we don’t really have to choose. People who want to are free to restrict calories through fasting, and also try pushing their exercise to the limit.
In my own case, I’m doing both exercising and periodic fasting, with the aim of slowing down the aging process. It does seem likely that slowing aging and postponing morbidity could keep us around long enough to take advantage of medical breakthroughs that appear to be on the horizon. There’s no way of knowing for sure how much difference what we’re doing will make, but I’m personally finding it fun to try.