Being lazy may be in your genes: study

Couch potatoes may be genetically predisposed to being lazy, according to a new study.

Certain genetic traits may predispose people to being more or less motivated to exercise and remain active, found the study by University of Missouri. Frank Booth, a professor in the MU College of Veterinary Medicine, along with Michael Roberts, were able to selectively breed rats that exhibited traits of either extreme activity or extreme laziness.

They said these rats indicate that genetics could play a role in exercise motivation,even in humans. “We have shown that it is possible to be genetically predisposed to being lazy,” Booth said. “It would be very useful to know if a person I genetically predisposed to having a lack of motivation to exercise, because that could potentially make them more likely to grow obese,” Booth said in a statement.

Researchers put rats in cages with running wheels and measured how much each rat willingly ran on their wheels during a six-day period.

They then bred the top 26 runners with each other and bred the 26 rats that ran the least with each other. They repeated this process through 10 generations and found that the line of running rats chose to run 10 times more than the line of ‘lazy’ rats.

Once the researchers created their ‘super runner’ and ‘couch potato’ rats, they studied the levels of mitochondria in muscle cells, compared body composition and conducted thorough genetic evaluations through RNA deep sequencing of each rat.

“While we found minor differences in the body composition and levels of mitochondria in muscle cells of the rats, the most important thing we identified were the genetic differences between the two lines of rats,” Roberts said.

“Out of more than 17,000 different genes in one part of the brain, we identified 36 genes that may play a role in predisposition to physical activity motivation,” Roberts said.

The study was published in the American Journal of Physiology: Regulatory, Integrative and Comparative Physiology.