NOVEL, HIGH-INTENSITY EXERCISE PRESCRIPTION IMPROVES MUSCLE MASS, MITOCHONDRIAL FUNCTION, AND PHYSICAL CAPACITY IN INDIVIDUALS WITH PARKINSON'S DISEASE

Neil A. Kelly, Matthew P. Ford, David G. Standaert, Ray L. Watts, C. Scott Bickel, Douglas R. Moellering, Steven Craig Tuggle, Jeri Y. Williams, Laura Lieb, Samuel T. Windham, Marcas M. Bamman

Abstract

We conducted, in persons with Parkinson's disease (PD), a thorough assessment of neuromotor function and performance in conjunction with phenotypic analyses of skeletal muscle tissue, and further tested the adaptability of PD muscle to high-intensity exercise training. Fifteen participants with PD (Hoehn & Yahr stage 2-3) completed 16 wk of high-intensity exercise training designed to simultaneously challenge strength, power, endurance, balance, and mobility function. Skeletal muscle adaptations (p<0.05) to exercise training in PD included: myofiber hypertrophy (type I:+14%, type II:+36%); shift to less fatigable myofiber type profile; and increased mitochondrial complex activity in both subsarcolemmal and intermyofibrillar fractions (I: +45-56%, IV: +39-54%). These adaptations were accompanied by a host of functional and clinical improvements (p<0.05): total body strength (+30-56%); leg power (+42%); single leg balance (+34%); sit-to-stand motor unit activation requirement (-30%); 6-min walk (+43m), Parkinson's Disease Quality of Life Scale (PDQ-39, -7.8pts); Unified Parkinson's Disease Rating Scale (UPDRS) total (-5.7pts) and motor (-2.7pts); and fatigue severity (-17%). Additionally, PD subjects in the pre-training state were compared to a group of matched, non-PD controls (CON; did not exercise). A combined assessment of muscle tissue phenotype and neuromuscular function revealed a higher distribution and larger cross sectional area of type I myofibers, and greater type II myofiber size heterogeneity in PD vs. CON (p<0.05). In conclusion, persons with moderately advanced PD adapt to high-intensity exercise training with favorable changes in skeletal muscle at the cellular and subcellular levels that are associated with improvements in motor function, physical capacity, and fatigue perception.

  • Parkinson's disease
  • high-intensity exercise
  • resistance training
  • muscle hypertrophy
  • mitochondria