But I’m Genetically Programmed to Be a Couch Potato
Did you ever notice that some people can’t wait to get to the gym, lace up their sneakers, and start a workout, while others find lots of excuses to avoid a day’s exercise, lingering at the drink bar and cutting their time on the treadmill short? Researchers from the University of Missouri College of Veterinary Medicine are looking into the genetics of loving or avoiding exercise.
Their experiment will be published later this year in the American Journal of Physiology: Regulatory, Integrative and Comparative Physiology. In this study, they took 159 rats to the gym — in this case, a room with rodent exercise wheels in a laboratory — and invited the rats to use the equipment. Some rats chose to run more than others. Researchers then took the rats who chose to run more and separated them from those who ran less. The rats were mated together, creating offspring from exercise lovers and offspring from exercise avoiders. Mating exercise lover with exercise lover and exercise avoider with exercise avoider continued for 10 generations.
As the researchers expected, rats born to parents from generations who loved the exercise wheel ran longer and faster when invited to exercise compared with those bred from the exercise avoiders. Despite these differences in exercise interest, both groups of rats had similar muscle anatomy and physiology. Both groups also ate the same amount of food. Exercise avoiding rats tended to weigh more and the lost less weight from exercise than the exercise lovers. Genetic tests showed important differences between the two groups, including differences in genes that affect motivation centers in the brain. The researchers are planning to conduct further studies to better define specific gene markers for exercise lovers versus exercise avoiders.
So when you look at your girlfriend, sibling, or coworker and wonder how she can enjoy working out so much when it seems like drudgery to you — the differences are likely to be in your genes. And if your genes don’t inspire you to exercise like you should, remember to enlist the aid of Nature’s best personal trainer — the one on the end of the leash. Research shows the best motivator for humans to exercise is your favorite dog. So even if you come from a long line of exercise avoiders, don’t let genes become your excuse. Whistle for Fido and get fit!