Study: NCT01058213

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: Resistance training
Description: Supervised training will be performed on a cable exercise system (Body Solid, Forest Park, IL) using six exercises that involve concentric and eccentric muscle actions: leg press, knee flexion, knee extension, calf raise, hip adduction, hip abduction. Subjects will perform the lower extremity exercises under the direct supervision of an exercise specialist three times per week. Subjects will perform 2 sets of 8-10 repetitions at 70% of their maximum strength for 2 weeks, then will perform 2 sets of 8-10 repetitions at 80% of their maximal strength for 2 weeks, and for the next 4 weeks they will perform 3 sets of 8-10 repetitions at 80% of their maximal strength. Sets will be separated by at least a 2-3 minute rest period for multiple-joint exercises and at least 1-2 minutes for single-joint exercises. A moderate velocity of muscle contraction (\~1-2 seconds for concentric and eccentric contraction) will be used.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Resistance training
Description: Supervised training will be performed on a cable exercise system (Body Solid, Forest Park, IL) using six exercises that involve concentric and eccentric muscle actions: leg press, knee flexion, knee extension, calf raise, hip adduction, hip abduction. Subjects will perform the lower extremity exercises under the direct supervision of an exercise specialist three times per week. Subjects will perform 2 sets of 8-10 repetitions at 70% of their maximum strength for 2 weeks, then will perform 2 sets of 8-10 repetitions at 80% of their maximal strength for 2 weeks, and for the next 4 weeks they will perform 3 sets of 8-10 repetitions at 80% of their maximal strength. Sets will be separated by at least a 2-3 minute rest period for multiple-joint exercises and at least 1-2 minutes for single-joint exercises. A moderate velocity of muscle contraction (\~1-2 seconds for concentric and eccentric contraction) will be used.

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: Aerobic training
Description: Cycle ergometry training will be performed in the lab on a stationary cycle ergometer, calibrated with a 4 kg weight (Monark 828E, Varberg, Sweden). Initial work rate will be 50% of peak work rate (PWR) as tolerated and will be evaluated weekly with progressive increases targeted to achieve the highest work rate tolerated for 3-5 minutes{: wks 1-2 50% PWR, wks 3-4 60% PWR, wks 5-6 70% PWR, wks 7-8 80% PWR}. An interval training protocol will be used with subjects performing four work sets of five minutes duration separated by rest intervals of unloaded cycling lasting 2-4 minutes.

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: Aerobic training
Description: Cycle ergometry training will be performed in the lab on a stationary cycle ergometer, calibrated with a 4 kg weight (Monark 828E, Varberg, Sweden). Initial work rate will be 50% of peak work rate (PWR) as tolerated and will be evaluated weekly with progressive increases targeted to achieve the highest work rate tolerated for 3-5 minutes{: wks 1-2 50% PWR, wks 3-4 60% PWR, wks 5-6 70% PWR, wks 7-8 80% PWR}. An interval training protocol will be used with subjects performing four work sets of five minutes duration separated by rest intervals of unloaded cycling lasting 2-4 minutes.

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Aerobic training
Description: Cycle ergometry training will be performed in the lab on a stationary cycle ergometer, calibrated with a 4 kg weight (Monark 828E, Varberg, Sweden). Initial work rate will be 50% of peak work rate (PWR) as tolerated and will be evaluated weekly with progressive increases targeted to achieve the highest work rate tolerated for 3-5 minutes{: wks 1-2 50% PWR, wks 3-4 60% PWR, wks 5-6 70% PWR, wks 7-8 80% PWR}. An interval training protocol will be used with subjects performing four work sets of five minutes duration separated by rest intervals of unloaded cycling lasting 2-4 minutes.