Hate exercise? You might blame your genes
If the thought of hopping on a treadmill strikes you with dread, you might have your genes to blame, researchers say.
A 2014 study showed that an appreciation for running was likely genetic. Researchers studied two groups of rats — low- and high-performing runners — to see how well their offspring ran. They found that the offspring’s fondness for running was consistent with that of their parents. Later generations of high-performing runners ran 10 times faster than the halfhearted group.
When it comes to exercise, there’s a lot that happens not only in the body but also in the brain, according to exercise science researcher Lorraine Turcotte, Gabilan Distinguished Professorship in Science and Engineering and professor of biological sciences at USC Dornsife College of Letters, Arts and Sciences. For some people, exercise just feels bad.
“Either it’s in the brain or it’s something biochemical in the muscle,” she said. “Something is different.”
For example, in that 2014 study, the avid runners had greater activity in the brain’s pleasure and reward center. When the avid runners ran, that portion of the brain lit up with activity. That didn’t happen in the lazy group.
Turcotte is studying the muscles of avid runners and less-active runners to look for differences in mitochondria — the power generators of cells. Findings could add to the conversation about links between genetics and exercise.
There’s also research that shows endorphins — which sometimes trigger euphoria after aerobic exercise — are fickle, Turcotte said. Some people never get a “runner’s high” from working out. And some people get an endorphin rush from less-active pursuits, like nerding out on scientific research, she added.
“There are a lot of things people prefer to do in life due to the release of endorphins,” she said. “Your passion is your chemistry.”