For years, research has shown that not all obese people are unhealthy. However, many have eschewed the studies, saying that obesity and being out of shape were inextricably linked.
Work at the Univ. of Michigan has two study groups to examine how exercise impacts the body. Both groups were adults with obesity. One group didn’t exercise, while the other worked out at least four times a week for two years. The researchers took samples of their belly fat tissue. Both groups had the same amount of body fat. However, their fat was not the same.
They examined the tissue to measure blood flow, inflammation, rigidity and fibrousness. People who exercised had more blood vessels in their fat tissue, allowing more oxygen flow. Their fat was less prone to inflammation and less rigid. Their fat cells were smaller, meaning they could store and release energy more efficiently.
Using blood tests and MRIs, researchers found that the exercises also had significantly better heart health. They had better insulin sensitivity and better levels of HDL cholesterol. And, they had healthier livers.
“Fat is really misunderstood,” said lead author Dr. Jeffrey Horowitz. “Our findings indicate that in addition to being a means to expend calories, exercising regularly for several months to years seems to modify your fat tissue in ways that allows you to store your body fat more healthfully if or when you do experience some weight gain – as nearly everyone does as we get older. We generally see these differences are more robust in people who exercise regularly for years versus those who don’t exercise.”
“People who exercise regularly appear to have much healthier subcutaneous adipose tissue, which would suggest that they have better overall metabolic function,” said Dr. Aayush Visaria, an internal medicine resident at Rutgers Robert Wood Johnson Medical School, who was not involved with the research. “It adds to the whole idea that obesity is a very complex subject with many variables involved, so we should not be making blanket statements about someone’s body type.”
Whenever work like this comes out, some say that it is just done to justify people being okay with being fat and not “make an effort.” That’s absurd. Dr. Horowitz said that his team’s work underscores the importance of an active life. He stressed that his team isn’t changing recommendations on health.
Dr. Horowitz said, “We’re expanding the understanding of why it is helpful to exercise.”
