Endurance exercise may be a counter measure for insulin sensitivity and aging

Mitochondrial dysfunction, reduced insulin sensitivity and other age-related dysfunctions may be controlled by endurance training.

The results emanated from a recent study published in Diabetes journal.

The study sample (n=42) consisted of sedentary and endurance trained young and old subjects. Insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp and ATP production in mitochondria isolated from tissue biopsies. As markers of aging, expression of proteins involved in fuel metabolism, Citrate synthase activity, expression of mitochondrial DNA (mtDNA) and other factors for mitochondrial biogenesis were analysed.

From the analysis it was found that endurance trained young and older subjects had a higher degree of endogenous glucose production suppression and insulin induced glucose disposal. Further, age-related decrease in mitochondrial oxidative capacity was not found in endurance-trained subjects.

Although, there was a higher expression of aging markers (mtDNA, mitochondrial proteins, and mitochondrial transcription factors) in endurance-trained individuals, there were persisting effects of age.

Reduced insulin sensitivity, which is related to changes in adiposity is dependent on physical inactivity but not on aging. Regular endurance-training helps in normalizing age-related mitochondrial dysfunction. Furthermore, physical activity may promote longevity.