title: Longitudinal study of skeletal muscle adaptations during immobilization and rehabilitation.
abstract: This study describes the metabolic, morphologic, neurologic, and functional adaptations observed in the plantar flexors during 8 weeks of lower leg immobilization and 10 weeks of physical therapy following ankle surgery. A combination of magnetic resonance imaging and spectroscopy, isokinetic and isometric muscle testing, and simple functional tests revealed many adaptive changes due to immobilization, including atrophy, loss of muscle strength, reduced central activation, increase in fatigue resistance, and an increase in inorganic phosphate content. After 10 weeks of physical therapy all alterations were reversed, with the exception of a remaining 5.5% deficit in total muscle cross-sectional area.
authors.affiliation: Department of Rehabilitation Medicine, University of Pennsylvania, Philadelphia 19104, USA.
authors.forename: K
authors.initials: K
authors.lastname: Vandenborne
authors.forename: M A
authors.initials: MA
authors.lastname: Elliott
authors.forename: G A
authors.initials: GA
authors.lastname: Walter
authors.forename: S
authors.initials: S
authors.lastname: Abdus
authors.forename: E
authors.initials: E
authors.lastname: Okereke
authors.forename: M
authors.initials: M
authors.lastname: Shaffer
authors.forename: D
authors.initials: D
authors.lastname: Tahernia
authors.forename: J L
authors.initials: JL
authors.lastname: Esterhai
mesh_terms: D000328:Adult; D016512:Ankle Injuries / Q000175:diagnosis / Q000503:physiopathology / Q000534:rehabilitation*; D001284:Atrophy; D001510:Bed Rest; D002370:Casts, Surgical; D050723:Fractures, Bone / Q000175:diagnosis / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007551:Isotonic Contraction / Q000502:physiology; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009043:Motor Activity / Q000502:physiology; D018482:Muscle, Skeletal / Q000473:pathology / Q000502:physiology*; D026741:Physical Therapy Modalities; D019415:Torque; D016138:Walking