title: Novel, high-intensity exercise prescription improves muscle mass, mitochondrial function, and physical capacity in individuals with Parkinson's disease.
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 and 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 (+43 m), Parkinson's Disease Quality of Life Scale (PDQ-39, -7.8pts); Unified Parkinson's Disease Rating Scale (UPDRS) total (-5.7 pts) and motor (-2.7 pts); and fatigue severity (-17%). Additionally, PD subjects in the pretraining state were compared with 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.
authors.affiliation: UAB Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama;
authors.forename: Neil A
authors.initials: NA
authors.lastname: Kelly
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Ford
authors.forename: David G
authors.initials: DG
authors.lastname: Standaert
authors.forename: Ray L
authors.initials: RL
authors.lastname: Watts
authors.forename: C Scott
authors.initials: CS
authors.lastname: Bickel
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Moellering
authors.forename: S Craig
authors.initials: SC
authors.lastname: Tuggle
authors.forename: Jeri Y
authors.initials: JY
authors.lastname: Williams
authors.forename: Laura
authors.initials: L
authors.lastname: Lieb
authors.forename: Samuel T
authors.initials: ST
authors.lastname: Windham
authors.forename: Marcas M
authors.initials: MM
authors.lastname: Bamman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000978:Antiparkinson Agents / Q000627:therapeutic use; D001823:Body Composition / Q000502:physiology; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D008875:Middle Aged; D008931:Mitochondria, Muscle / Q000502:physiology*; D009046:Motor Neurons / Q000502:physiology; D018763:Muscle Fatigue / Q000502:physiology; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010300:Parkinson Disease / Q000503:physiopathology* / Q000628:therapy*; D010349:Patient Compliance; D055656:Prescriptions; D011569:Psychiatric Status Rating Scales; D011788:Quality of Life; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents
keywords: Parkinson's disease; high-intensity exercise; mitochondria; muscle hypertrophy; resistance training