A new study shows how exercise can help rejuvenate aging muscles. Doctors call exercise a “polypill” because it can prevent and treat many of the chronic diseases associated with aging.
A new study of mouse and human muscle fibers shows how exercise affects gene expression. The exercise-induced changes “reprogram” the epigenetic expression of the fibers to a more youthful state. The findings might provide avenues for developing drugs to mimic these benefits in people who can’t exercise.
Research shows that people who exercise regularly not only build muscle, but also improve their overall health, regardless of when in life they start. For example, recent studies have shown that exercise reduces the risk of cardiovascular disease, as well as Alzheimer’s and Parkinson’s disease in older people.
Conversely, reduced muscle mass and strength are associated with lower quality of life and higher all-cause mortality. Because of its proven ability to prevent and treat several chronic diseases at low cost, doctors have dubbed exercise a drug-free “polypill” that almost anyone can benefit from.
Exercise should be seen as a health-enhancing and life-prolonging treatment, along with medication and healthy eating. Scientists hope that a better understanding of how exercise rejuvenates aging muscles at the molecular level will provide clues for future anti-aging therapies.
Reprogram muscle fibers
Exercise can turn back the clock in muscle fibers by promoting the “epigenetic reprogramming” of chromosomes in cell nuclei. Epigenetics refers to how chemical changes affect the activity or “expression” of genes. For example, proteins called transcription factors can stimulate the expression of certain genes when they bind to specific DNA sequences. In 2012, Dr. Shinya Yamanaka was awarded the Nobel Prize in Medicine for his discovery that four transcription factors can transform specialized, mature cells into younger, more flexible cells called pluripotent stem cells. These four factors are called Oct3/4, Klf4, Sox2 and Myc, or OKSM for short.
In a new study whose results are published in The Journal of Physiology, researchers compared the effects of OKSM factors on gene expression in the muscle fibers of mice that had access to an exercise wheel and mice that did not. didn’t have access to it. In addition, they compared the effects of OKSM factors on muscle with the effects of a single transcription factor, Myc. The scientists found that exercise induces Myc expression to a greater extent than the other three factors.
The researchers also studied how exercise alone affected gene expression in the muscle fibers of mice and humans. The mice were 22 months old, which equates to a human age of regarding 73 years. The mice in the “exercise” group were free to run on an unweighted wheel for the first week, then, over the next eight weeks, the scientists gradually weighed down the wheel by attaching magnetic weights to it. The results suggest that exercise reprograms muscle fibers to a more youthful state through increased expression of genes that make Yamanaka factors, particularly Myc.
A supercharged response to exercise
These findings might one day lead to the development of drugs that supercharge the exercise response of the muscles of people confined to bed or the muscles of astronauts in weightlessness.
But don’t think that a pill that boosts Myc expression can ever replace the need to exercise. For one thing, exercise benefits the whole body, not just the muscles. In addition, the Myc protein has been associated with cancer, so artificially increasing its expression carries inherent risks. In their paper, the researchers also note that drugs that are gaining a popular reputation for “life extension” may actually block some of the beneficial effects of exercise on muscles.
exercises for the elderly
What is the best type of exercise for older people.
For people over 70, I would highly recommend low impact, full body workouts with a focus on the lower body and core. Resistance training is not only suitable but also highly recommended for people in their 70s and the elderly. The key is to start slowly and progress slowly with consistency. In terms of frequency, an elderly person can walk every day, assuming he has no contraindications. Strength training at least two days a week and mobility training, including stretching, every day is a good program.
