Weight loss theory debunked – exercise a bigger weapon against obesity than diet

In the debate over the roles of exercise and diet in weight loss, one argument is that exercise does not play a significant role as it increases appetite, resulting in greater food intake, and potentially reduces activity through the day. A University of Missouri study proves this theory wrong, showing that exercise has significant impact on fat tissue, metabolism and gut microbes.

Researchers divided young rats prone to obesity into three groups. All three groups were fed a high-fat diet. Two of the groups were sedentary while the third group was able to exercise using running wheels. Of the two sedentary groups, one was allowed to eat as much of the high-fat food as they wanted, while the other group were fed controlled portions of the food in order to match the weight reduction caused by exercise. The exercising rats were allowed to eat as much as they wanted.

Several weeks later, the sedentary rats with unlimited food access were unsurprisingly obese. Notably, the exercising rats were metabolically healthier and developed different gut microbes than both of the sedentary groups, despite eating the exact same amount of food as the sedentary group with unlimited food access. Overall, the exercising rats had higher metabolic rates, were more active even when not running on their wheels and experienced shifts in their gut microbes, perhaps putting them in a better position to avoid future weight gain compared to the other groups.