Stephen Kintz
Mar 18, 2012
Featured

Exercise alters DNA

Men compete in a 100-meter dashExercise alters your DNA  ... well, sort of. Your DNA is not really altered. Exercise cannot rewrite your genetic code. I’m sorry, but exercising will not cause you to mutate into a superhero, so if you want to be a superhero, you should continue with your daily dose of radioactive waste or hanging around genetically altered spiders.

So what did the study find?

The study conducted by Juleen Zierath, Romain Barrès and colleagues at the Karolinska Institute in Stockholm, Sweden found that exercise reduces DNA methylation within muscle tissue. DNA methylation is a biochemical process that regulates how DNA is expressed and decoded. When the DNA methylation is reduced, proteins’ transcription factors could more readily access the DNA and produce proteins to support muscle growth and metabolism. Therefore, exercise leads to muscle growth and higher metabolism.

A man on a treadmillOf course, the researchers did not stop there. They wanted to understand what caused the DNA methylation to decrease in the muscle tissue, and they had a suspicion that DNA methylation was reduced by calcium deposits in the muscle tissue being release during exercise. To test whether calcium is the culprit, the researchers flushed rats’ muscle tissue with high doses of caffeine, which also causes muscle tissue to release calcium. The researchers found that the rats had reduced levels of DNA methylation.

So why is this research important?

This research does not make any grand revelations about the health benefits of exercise. More importantly, it does not suggest that you can forgo exercise for caffeine. You would have to drink lethal amounts of caffeine to see any benefits, and death would probably reduce your enjoyment of your new ill-gotten biceps. Basically, this research describes the biological mechanisms that make exercise beneficial.

In fact, this is just one recent study in an explosion of research that is beginning unravel how the body maintains itself and repairs itself. Another study from Harvard University conducted by Bruce Spiegelman and colleagues has isolated a key hormone, which they named irisin, which coverts energy storing white fat into energy burning brown fat. It was not too long ago that scientists thought new brown fat was only produced in babies. Now, scientists not only understand the purpose of brown fat but are beginning to unravel how white and brown fats are developed.

Female runnersBoth these studies are not only showing the importance of exercise to maintaining a healthy lifestyle, but they are offering future researchers potential treatments for obesity, diabetes and high blood pressure. In a world where the World Health Organization classifies over 1.5 billion people as obese and economic growth appears to lead to greater waistlines, it is becoming more and more important to find treatments for obesity.

Hopefully, future researchers can use the biological mechanisms discovered by Juleen Zierath, Romain Barrès and colleagues to produce drugs that reduce DNA methylation and promote muscle growth and higher metabolism. In fact, Bruce Spiegelman and colleagues have already tried injecting mice with the irisin hormone, and the researchers found that the mice burn fat without any noticeable side effects.

So in a few years, we might be able to get the tone muscles and slim waist lines that we all want while maintaining a ridiculously sedentary and high fat lifestyle. Of course, until then, we should all probably take this research as a good reminder that we evolved to move, so we should exercise.