The purpose of this study was to investigate the effects of a progressive resistance training program on myosin heavy chain isoform expression, fiber type, and capillarization in patients with symptomatic peripheral arterial disease. Patients were randomized to either a training group (n = 11, mean +/- SD, 70 +/- 6 years, 4 men, 7 women) or a control group (n = 9, 66 +/- 6 years, 5 men, 4 women). The training sessions were completed 3 times/week, using 2 sets of various exercises, each performed for 8-15 repetitions. Muscle biopsies were obtained before and after 24 weeks from the medial gastrocnemius. Following the 24-week training program, the training group had significantly decreased the percentage of myosin heavy chain type IIB. The proportion of type IIB/AB fibers as measured by using myosin adenosine triphosphatase histochemistry decreased significantly in the training group. There were significant increases in type I and type II fiber areas, and capillary density also increased significantly in the training group. There were significant increases in 10 repetition maximum leg press and calf press strengths in the trained subjects. There were no significant changes in any of the measurements in the control group. It is concluded that progressive resistance training results in significant increases in muscle strength and alters skeletal muscle composition of subjects with peripheral arterial disease.
This study showed a significant modification in the expression of MHC isoforms and muscle fiber type in the gastrocnemius in patients with symptomatic PAD. These results suggest that muscle ischemia resulting from PAD is an important factor in causing the adaptations in the contractile apparatus of the muscle.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.