A team of researchers has found that people who do extreme fitness suffer from impaired mitochondrial functionDevelop insulin resistancecan. In their recently published article, the group describes exercise experiments they conducted with volunteers and what they learned from them.
Increased risk of diabetes due to extreme fitness
Most health experts recommend that their patients exercise regularly and do more sports. However, in current studies, researchers have found that the body's options are limited. Too much training can lead to insulin resistance and mitochondrial dysfunction. To learn more about how the body responds to exercise, the team developed an extreme training program to test the body's limits. The scientists then enlisted the support of 11 healthy young volunteers. However, the subjects had already kept themselves in shape through some form of exercise. The experiment had three phases. Volunteers rode exercise bikes for specific periods of time over a four-week period. In the first phase, all volunteers exercised at high-intensity intervals over a period of 36 minutes. In the second phase, the training duration increased to 90 minutes.
During the third phase, study participants trained for 152 minutes over a week. In the experiment, researchers collected muscle biopsies from each of the volunteers to measure mitochondrial function. Each subject also underwent blood glucose testing to monitor insulin resistance. As expected, the study authors found that insulin remained at normal levels during phases one and two of the experiment. They also found that mitochondrial function improved in the first two phases. Previous research has shown that regular exercise is good for this. However, the third phase showed that most volunteers had insulin resistance similar to that of a person suffering from diabetes. Mitochondrial respiration decreased by an average of 40% compared to the samples taken during the first phase of the experiment. Therefore the results showthis studythat excessive exercise could increase the risk of diabetes.
