Muscle Insulin Resistance in Aging (Mirage)

Participants will complete a progressive 6-month exercise training program, 4-5 days per week, 45 min per session (180 min per week), consisting mostly of walking (both outside and on an indoor treadmill) but with the option to include stationary cycling, elliptical and rowing machines, similar to what we have utilized previously to elicit significant improvements in insulin sensitivity in both middle-age and older adults (52-55). Beginning at week 8, these subjects will also perform 2 non-consecutive resistance exercise sessions per week, 30 min per session, focused on major muscle groups using resistance machines (total days of exercise will still be 4 to 5).

The goal of the weight loss intervention will be to produce a weight loss of 10% body weight. A reduction of 500-1000 kcal/day - based on baseline weight -and low fat (\<30% of calories from fat) diet will be used as part of the weight loss intervention.