Slowing down aging has always been a topic of great concern to people; ancient emperors even went so far as to expend enormous material and human resources to sail the seas in search of elixirs of immortality. To explore the mechanisms of aging, scientists have proposed a series of hypotheses, including the oxygen free radical theory, the telomere theory, the cumulative DNA damage theory, and the gene regulation theory. The mitochondrial aging theory posits that as we age, mitochondrial function gradually becomes abnormal, which is a hallmark of aging in many species, including humans.
The journal Nature Communications published a study exploring the relationship between exercise and the delay of aging. The research suggests that exercise enhances the expression of the mitochondrial hormone MOTS-c in the human body. When scientists injected MOTS-c into mice, it improved their physical function, regulated metabolism during the aging process, and may even extend healthy lifespan.
MOTS-c is a type of mitochondria-derived peptide found in various tissues and the circulation (plasma) of rodents and humans; it is known as a “mitochondrial hormone.” Researchers divided mice into three groups—young (2 months), middle-aged (12 months), and elderly (22 months)—and injected them with MOTS-c. They found that mice of all age groups injected with MOTS-c performed better on physical tests—including maintaining balance on a rotating rod and running on an accelerating treadmill—than control mice of the same age. Mice fed a high-fat diet showed significant improvements in physical condition after receiving MOTS-c injections, gaining less weight than the control group. The study also found that MOTS-c administration can reverse diet-induced obesity as well as diet- and age-dependent insulin resistance.
To investigate the effects of exercise on MOTS-c levels in humans, the researchers recruited healthy, young, sedentary men. The participants exercised on stationary bicycles, and skeletal muscle and plasma samples were collected before, during, and after exercise, as well as 4 hours after rest. The study found that MOTS-c levels in muscle cells increased nearly 12-fold after exercise and remained elevated even after a 4-hour rest period; MOTS-c levels in plasma also increased by about 50% during and after exercise, returning to normal levels after the rest period. Aging is regulated by mitochondria and the genes in their genomes, and MOTS-c can delay aging by promoting cellular homeostasis, thereby promoting longevity.
So, what is the most “cost-effective” form of exercise?
Sammi R. Chekroud of the University of Oxford and colleagues published a cross-sectional study in Lancet Psychiatry examining the association between physical activity and mental health in the United States from 2011 to 2015, involving a total of 1.2 million participants. *A cross-sectional study is a research method that collects and describes data on the distribution of diseases or health conditions and related factors among a population at a specific point in time and within a specific scope, providing clues for further research into causality. It is the most widely used research method in descriptive epidemiology. This study examined the relationship between physical exercise and the burden of mental health issues in a large sample to better understand the effects of exercise type, frequency, duration, and intensity. The study found that team exercises, aerobic exercises, and cycling were most beneficial for mental health, while racket sports—such as tennis and badminton—reduced all-cause mortality by 47%. Furthermore, racket sports and aerobic exercises were not only most beneficial for mental health but also highly beneficial for physical health.
By examining the relationship between exercise duration and physical health, Chekroud discovered that longer exercise sessions do not necessarily equate to better physical health. For the average person, it’s best to engage in racket sports, aerobic exercises, cycling, swimming, and similar activities 3–5 times a week—once a day is sufficient. The optimal duration per session is 45–60 minutes; if it’s less than 45 minutes, the benefits diminish, and if it exceeds 60 minutes, not only does it fail to provide additional benefits for physical and mental health, but it can also have negative effects. Of course, if you’re walking, you can exercise a bit more frequently each week, but it’s best not to exceed six times. It seems that exercise is the most effective and cost-effective way to slow down aging—so what excuse do you have for just “lying around” every day?