A recent study, published in Cell Metabolism, and conducted by researchers at the Karolinska Institute, demonstrates that exercise almost immediately alters DNA in healthy inactive men and women.
The researchers explain that although the genetic makeup is not altered, DNA molecules change structurally and chemically when a person exercises. An example of this is the DNA gaining more or losing parts of methyl groups that are found on sequences of DNA families.
Juleen Zierath, Professor of Clinical Integratice Physiology at the Department of Molecular Medicine and Surgery says:
"Our muscles are really plastic. We often say 'You are what you eat.' Well, muscle adapts to what you do. If you don't use it, you lost it and this is one of the mechanisms that allow that to happen."
During the study, DNA within skeletal muscle was taken from people who had just experienced a round of exercise. The DNA showed less methyl groups than it had before the person's work out. The changes were found in the areas of DNA which work as stopping places for a certain kind of enzymes, called transcription factors. These enzymes are very important in terms of muscles and exercise.
"Exercise is already known to induce changes in muscle, including increased metabolism of sugar and fat. Our discovery is that the methylation change comes first."
The authors explain that transcription factors basically open our genes. When methyl groups are secure, the transcription factors are not able to enter through DNA. However, when the methyl groups are not in place, the transcription factors can move about freely and therefore the muscle is able to work harder.
During their study, Zierath, and team placed muscles in lab dishes, and made them contract, noticing that they were lacking methyl groups, which was similar to what happened when the muscles were exposed to caffeine. This is because caffeine makes muscles give off calcium, which has the same effect that muscles have when they are exercised.
The researchers do not recommend that anyone should drink caffeine beverages instead of exercising; exercising has many more beneficial health effects.
"Exercise is medicine, and it seems the means to alter our epigenomes for better health may be only a jog away."