Grant: Doctoral Research Award: Canada Graduate Scholarships

Aging and family history of diabetes are recognized as risk factors for type 2 diabetes. The accumulation of fat within the muscle and the inability to sufficiently utilize this fat source are amongst the proposed mechanisms to explain this increased risk. A potent intervention to prevent type 2 diabetes in various populations is aerobic exercise. However, individuals with a family history of diabetes are known to have reduced fat oxidation at rest and during submaximal exercise. Furthermore, recent results from our research group suggest that a greater proportion of fat-derived energy would be drawn from the blood at the expense of fat stored in the muscles. Together, these metabolic alterations could potentially limit the exercise-induced benefits on type 2 diabetes prevention. Our recent observations were however drawn from indirect methods and we thus wish to confirm our results with a more appropriate study design. Our objectives are to verify if : 1) Aging women with a family history of type2 diabetes utilize less fat stored in the muscle relative to fat in blood circulation, compared with aging women without a family history of diabetes. 2) To determine the exercise intensity at which the utilization of fat stored in the muscle is at its peak. Studies investigating exercise metabolism in individuals with family history fo type 2 diabetes are scarce and, to the best of or knowledge, inexistent in an aging population. Our study would thus be the first to investigate how different sources of fat are used during exercise in a population at high risk for type 2 diabetes. Results from this study will guide us in a future project assessing the impact of different exercise modalities on fat oxidation and their impact on glycemic control.