Exercise can positively alter subcutaneous adipose tissue, which can improve metabolic health.

Exercise is one of the first strategies used to treat obesity-related health problems like type 2 diabetes and other cardiovascular diseases, but scientists don’t understand exactly how it works to improve metabolic health.

To that end, researchers at the University of Michigan examined the effects of three months of exercise on obese people, and found that exercise positively alters the adipose tissue beneath the skin, even in ways that improve metabolic health. Without losing weight.

Interestingly, moderate and high-intensity exercise produce similar positive changes in fat tissue composition and structure, and fat cells shrink slightly even without weight loss, said lead investigator Jeffrey Horowitz, UM kinesiology professor.

The findings are published in the Journal of Physiology. Primary authors are UM doctoral student Cheehoon Ahn and Ben Ryan, a UM graduate research fellow currently at the US Army Research Institute of Environmental Medicine.

Exercise changes how fat tissue looks and behaves.

The study aimed to better understand the effects of exercise on metabolic health in obese people. 36 obese adults were randomly assigned to either a moderate-intensity exercise group (45 minutes, 70% maximum heart rate) or a vigorous-intensity exercise group. low-intensity active recovery).

Blood samples and abdominal fat biopsies were collected the day after the completion of the 12-week sessions and again three days later. There was no exercise between these trials. Results for both exercise groups showed many structural changes in adipose tissue, including smaller fat cells and more, increased collagen type, increased capillary density, and changes in proteins that regulate body fat remodeling.

Horowitz noted that many of the changes observed one day after exercise that regulate body fat regulation were not significant on day 4 testing, indicating the importance of regular and sustained exercise.

Improvements are lost when exercise is stopped.

Adapting to multiple exercises is effective in allowing a person to exercise longer or harder, Horowitz said.

However, for people at risk of metabolic health problems or people with metabolic disease, most of the benefits of exercise that improve exercise are derived from the response to each exercise session—and the responses to exercise are relatively short-lived, usually lasting a few days at most. This is one big reason why it is so important to exercise on most days.

Jeffrey Horowitz, UM kinesiology professor

The finding that moderate- and high-intensity exercise produces similar responses may be good news for those who choose to avoid the more demanding high-intensity interval training, or HIIT.

Moderate exercise is just as beneficial as HIIT.

“Our findings suggest that options are open,” Horowitz said. “The similar response between HIIT and conventional moderate-intensity exercise was a big surprise to us. Despite the large differences in exercise stimulation (exercise time, cost, intensity) between these two training programs, it is remarkable that we observed very similar responses.

While the findings aren’t related to weight loss, they are related to metabolic health and disease prevention in obese people, which in turn affect quality of life, Horowitz said.

“Although some of our positive results are relatively short-lived, some are long-lasting, such as adipose tissue and fat cell structure,” he said. “So we think that an active lifestyle can help prevent some chronic metabolic health problems as people age, and evidence shows that most of us, even regular exercisers, gain weight as we age,” he said.

Horowitz says it’s important to understand that fat tissue is simply where the body stores extra energy and is not the reason people gain weight.

“Weight gain can only happen if you eat more calories than you burn. And when we gain weight, especially when people are approaching or moving toward obesity, it’s best to have healthy fat tissue to store this extra energy.”

Several of his labs’ recent studies, and a new five-year NIH-funded project that will soon begin, focus on understanding how exercise effectively damages adipose tissue to make it a safe place to store fat once people gain weight and time. Gaining or regaining weight.