Originally published on http://www.bicycling.com
https://www.bicycling.com/training/cycling-reverses-aging-muscles-immune-system
It might not grant eternal youth, but cycling, scientists have found, can slow the aging process and keep your muscles and immune system healthy well into your golden years.
Aging, it turns out, can do a number on your muscles. Humans typically lose muscle mass as they get older. Fat and connective tissue also start invading, affecting the muscles’ ability to contract. Furthermore, muscles can no longer suck up oxygen at the same rates.
However, a new study questioned if these age-related muscle declines are inevitable, or if regular exercise—cycling, in this case—can slow down or even reverse them.
To figure this out, researchers at King’s College in London biopsied the vastus lateralis muscle—the largest and most powerful part of the quad—in 125 male and female cyclists. Participants were all between 55 and 79 years old and deemed highly active (meaning the men could bike at least 62 miles at 15 mph, and the women 37 miles at 7 mph, twice within three weeks).
The researchers then analyzed muscle properties related to aerobic function and explosive muscle power. They found that, compared to sedentary populations, the cyclists showed less age-related muscle deterioration. That is, at the tissue level, muscle mass and strength stayed intact.
A second study turned the researchers’ attention to the immune system, which can also decline as you age. Specifically, your thymus—the part of your body that produces white blood cells—begins to shrink. It then produces fewer cells, meaning your body gradually loses the ability to protect itself against disease.
This trend, however, has been observed primarily in inactive populations, so the researchers wanted to see whether regular cycling could help prevent it. They compared blood samples from the same group of cyclists with blood from 75 older sedentary adults (aged 57-80) and 55 younger sedentary adults (aged 20-36).
They found that while cycling didn’t protect against every single measure of immune-system decline, the cyclists had white blood cell levels comparable to those of the younger control group—meaning that their immune systems were acting “younger.”
These studies are only two of many that demonstrate how physical activity like cycling can slow the aging process. One 2017 study found that high-intensity interval cycling increased mitochondrial capacity—a big deal when it comes to aging, as the decline of these organelles leads to the onset of age-related disease.
Another study from last year found that regular vigorous exercise protected telomere length. Shortened telomeres are what cause cell death—i.e., aging—and those who exercised saved themselves up to nine years of cellular deterioration.
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