Exercise improves our quality of life and reduces the risk of suffering from some diseases, such as diabetes or heart disease.
For example, eating certain types of diets or being exposed to pollutants, can change the way in which some of the genes in our DNA are expressed, and then affect the proteins that express these genes.
Depending on which genes are involved, this may have consequences on our health and the risk of suffering from some diseases.
Now, the results of new research show that exercise also changes the form and functioning of some of our genes.
Scientists from the Karolinska Institute in Stockholm recruited 23 people who underwent a series of tests to assess their physical performance and health exams, including a muscle biopsy, and then they were asked to practice certain exercises for three months.
The exercise consisted in using a bicycle using only one leg, without exercising the other.
The volunteers pedaled with one leg at a moderate pace for 45 minutes, four times a week for three months. After this period the muscle biopsies were repeated.
Obviously, after this time, the exercised leg had physical improvements that the untrained leg did not have.
Everything seems to be in the genes.
Using a sophisticated genomic analysis, the researchers observed the existence of changes in more than 5,000 sites in the genome of muscle cells of the exercised leg, which were not found in the non-exercised leg.
Interestingly, many of these changes were in enhancer genes, that is, they can amplify the expression of certain proteins.
Most of these genes play a fundamental role in energy metabolism, insulin response and inflammation within the muscles, ie factors related to the physical improvements observed in the exercised leg.
These genes did not change in the non-exercised leg.
More studies are needed to determine if the genetic changes observed in the exercised leg persist after stopping exercise, or to know how the amount or different types of exercise can affect gene expression patterns.