• Researchers say that regular exercise could promote healthful changes to how the body stores fat.
• In a small study, people with overweight and obesity who exercised stored less damaging subcutaneous fat and less hormone-disrupting visceral fat.
• The study builds on a body of research promoting the benefits of exercise regardless of weight, though more research is required.

Not all belly fat is created equal.

Subcutaneous fat, the soft fat that sits under the skin, is generally seen as less harmful than visceral fat, which collects deeper in the abdominal cavity and surrounds internal organs like the liver and kidneys. Visceral fat can increase insulin resistance and raise diabetes risk.

Now, new research published on September 10 in Nature Metabolism suggests that regular long-term exercise could improve how the body stores fat.

Researchers from the University of Michigan found that people with overweight and obesity who exercised regularly for at least two years had a greater capacity to store fat subcutaneously compared to a cohort with overweight and obesity who did not exercise.

This means exercisers could have a lower risk of accumulating more harmful visceral fat, regardless of weight gain.

“While abdominal subcutaneous adipose tissue (aSAT) and visceral fat contribute differently with overlaps to metabolic functions and balance, visceral fat is always more dangerous due to its hormonal activity, potential to cause dyslipidemia, and tendency to make clots,” Jagdish Khubchandani, PhD, a professor of public health at New Mexico State University, told Healthline. Khubchandani wasn’t involved in the study.

Exercise improves fat storage, but more research is needed

The study was small and only looked at 16 people who exercised compared to 16 people who didn’t, which may warrant further investigation.

“This was a reasonably well-designed study, though total numbers are relatively small,” Mir Ali, MD, board certified bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, told Healthlline.

“Though [the findings are] interesting, the significance of this change and why it matters is not well delineated. The authors surmise the change in subcutaneous fat may ‘contribute to preserved cardiometabolic health’ though the reason for this is not clear,” he continued.

Lead study author Jeffrey Horowitz, PhD, a professor of movement science and director of the Substrate Metabolism Laboratory at the University of Michigan School of Kinesiology, agreed the findings are worthy of further study.

“Although our study does not provide direct evidence to support this notion [of preserved cardiometabolic health], the general hypothesis is that is that if a person with obesity has an increased capacity to expand their subcutaneous adipose tissue to store their excess energy, less would be available to accumulate in tissues like their liver, heart, pancreas, etc., which is known to be very problematic in terms of metabolic health,” he told Healthline.

“Subjects in our exercise group were also more insulin sensitive and had other more favorable health outcomes compared with our non-exercise group (despite being well-matched for fat mass and other important parameters) — this indirectly supports our hypothesis, but certainly is not conclusive,” Horowitz continued.

Exercise is important for any weight loss program 

The study adds to a large body of evidence affirming the benefits of regular exercise regardless of a person’s weight.

But some experts say the focus should be on losing weight, rather than improving how the body stores fat.

“In general, for people who are overweight or obese, the goal is not promoting good versus bad fat storage but reducing fat stores in the body overall,” Ali said.

“Reducing visceral fat and overall fat has many health benefits, including reducing the risk for adverse health conditions such as diabetes, cardiac disease, and hypertension. In addition to exercise, a diet low in carbohydrates and higher in protein and non-starchy vegetables is a good way to direct the body toward burning the fat stores,” he continued.

Horowitz agreed but said the situation is more complex.

“Based on findings from studies from my lab and many others is that depending on the magnitude of fat loss, the improvements resulting from body fat loss are often profoundly more robust than improvements found after exercise training without weight loss,” he said.

However, those improvements are not always realistic for everyone. In the United States, where nearly three out of every four adults has overweight or obesity, lifestyle modifications must be practical.

“Sustained weight loss is often very challenging — and our findings suggest that living a physically active lifestyle can lead to a more ‘healthy’ way to store the body fat we have — which is likely an additional contributor to the health benefits of exercise,” Horowitz said.

Most people can fit regular movement and exercise into their schedules, even just a few days a week or on weekends. Some exercise is better than no exercise at all.

“The one thing that all of us can do without spending a lot of money is to manage stress, try to get adequate sleep, reduce technology use, walk daily and stay active, avoid isolation and loneliness, and stay optimistic,” Khubchandani said.

Takeaway

According to research, exercise changes how the body stores fat.

Results from the small study showed regular exercise led to healthier subcutaneous fat and reduced the likelihood of storing harmful visceral fat.

For people with overweight and obesity, losing weight and maintaining a healthy weight remains important for overall health. Still, regular exercise is often helpful, as this new study shows.

While more research is needed to confirm the overall cardiometabolic effects of these findings, the study adds to existing evidence showing the health benefits of exercise.