We all know that exercising can help us prevent many illnesses and make us fitter. What we don’t know is how exercising actually translates into a healthier life. A new study shows that the answer for this question might be hidden in our DNA. The study shows that exercising changes the function and shape of our genes and that leads to better health. The human genome is dynamic and really complex – genes are constantly turning off and on. When our genes are turned on, they express proteins that prompt physiological responses elsewhere in the body.
Scientists are certain that exercising can cause genes to become more active or quieter but they’re not sure how those same genes know how to respond to exercise.
Epigenetics is the process by which the gene’s operations are changed, but not the DNA. This change occurs on the outside of the genes through a process called methylation. In methylation, methyl groups which are actually clusters of atoms, attach to the outside of the gene and make the gene more or less able to receive/ respond to biochemical signals from your body.
Scientists are certain that lifestyle can cause changes in the methylation patterns. Being exposed to pollutants or eating a certain diet can cause changes in the methylation patterns on some of the genes and affect what proteins those genes express. This can also affect our health and put us at risk of getting certain illnesses, depending on the genes involved.
Some other, small studies have found that even a single exercise causes changes in the methylation patterns in certain genes in your muscle cells.
Scientists from the Karolinska Institute of Stockholm did a research where they recruited 23 healthy and young men and women. They brought the recruiters to the lab for a series of medical and physical performance tests, including muscle biopsy. The recruiters were asked to exercise half of their lower bodies for 3 months. The scientists told the volunteers to use the bicycle with only one leg and leave the other leg unexercised. This way both of their legs would undergo methylation patterns, but only the pedaling leg will show changes due to exercising.
The recruiters paddled with one leg for 45 minutes, 4 times a week per 3 months. After 3 months, the scientists did new muscle biopsies.
The research showed that the exercised leg was stronger than the other and that the exercising led to physical improvement. The more intriguing changes happened in the muscle cells’ DNA. More than 5000 sites on the genome of the muscle cells from the exercised leg had new methylation patterns. The changes were not found in the unexercised leg.
Many mysteries will still remain, but the message of this study is unambiguous.
“Through endurance training — a lifestyle change that is easily available for most people and doesn’t cost much money. We can induce changes that affect how we use our genes and, through that, get healthier and more functional muscles that ultimately improve our quality of life, “ explains the leader of the study, Malene Lindholm.