Exercise Rejuvenates the Body
Strength training specifically prompts the body to produce stem cells that repair motochondria, promotes the production of telomerase to maintain DNA, increase lifespan by six to seven years, and improve cognitive function dramatically as we age.
As noted earlier, mitochondrial degradation is a primary culprit in dwindling muscle mass. But recent evidence indicates that exercise can slow down this effect. According to Mark Tarnopolsky, a professor of pediatrics and medicine at McMaster University in Hamilton, Ontario, resistance training activates a muscle stem cell called a satellite cell. In a physiological process known as ‘gene shifting,' these new cells cause the mitochondria to rejuvenate. Tarnopolsky claims that after six months of twice weekly strength exercise training, the biochemical, physiological and genetic signature of older muscles are "turned back" by a factor of 15 to 20 years. That's significant — to say the least.
Studies involving middle-aged athletes indicate that high intensity exercise protects people at the chromosomal level as well. It appears that exercise stimulates the production of telomerase, what allows for the ongoing maintenance of genetic information and cellular integrity. Exercise also triggers the production of antioxidants, which boosts the health of the body in general.
And indeed, other studies are successfully linking athleticism to longevity. A recent analysis published in Deutsches Ärzteblatt International of more than 900,000 athletes (ranging in age from 20 to 79) showed that no significant age-related decline in performance appeared before the age of 55. And revealingly, even beyond that age the decline was surprisingly slow; in the 65 to 69 group, a quarter of the athletes performed above average among the 20 to 54 year-old group.
Essentially, exercise helps the body regenerate itself. This likely explains why older athletes are less susceptible to age-related illnesses than their sedentary counterparts. Moreover, ongoing exercise has been shown to preserve lean tissue, even during rapid and substantial weight loss. It also helps to maintain strength and mobility, which can significantly reduce risk of injury and stave off health problems that would otherwise linger.
Even more remarkable is how resistance training can stave off cognitive decline — what is arguably just as important as physical well being. In a study led by Teresa Liu-Ambrose of the University of British Columbia, women between the ages of 70 and 80 who were experiencing mild cognitive impairment were put through 60-minute classes two times per week for 26 weeks. They used a pressurized air system (for resistance) and free weights, and were told to perform various sets of exercises with variable loads. The results were remarkable: Lifting weights improved memory and staved off the effects of dementia. It also improved the seniors' attention span and ability to resolve conflicts.