title: Higher serum 25-hydroxyvitamin D concentrations associate with a faster recovery of skeletal muscle strength after muscular injury.
abstract: The primary purpose of this study was to identify if serum 25-hydroxyvitamin D (25(OH)D) concentrations predict muscular weakness after intense exercise. We hypothesized that pre-exercise serum 25(OH)D concentrations inversely predict exercise-induced muscular weakness. Fourteen recreationally active adults participated in this study. Each subject had one leg randomly assigned as a control. The other leg performed an intense exercise protocol. Single-leg peak isometric force and blood 25(OH)D, aspartate and alanine aminotransferases, albumin, interferon (IFN)-γ, and interleukin-4 were measured prior to and following intense exercise. Following exercise, serum 25(OH)D concentrations increased (p < 0.05) immediately, but within minutes, subsequently decreased (p < 0.05). Circulating albumin increases predicted (p < 0.005) serum 25(OH)D increases, while IFN-γ increases predicted (p < 0.001) serum 25(OH)D decreases. Muscular weakness persisted within the exercise leg (p < 0.05) and compared to the control leg (p < 0.05) after the exercise protocol. Serum 25(OH)D concentrations inversely predicted (p < 0.05) muscular weakness (i.e., control leg vs. exercise leg peak isometric force) immediately and days (i.e., 48-h and 72-h) after exercise, suggesting the attenuation of exercise-induced muscular weakness with increasing serum 25(OH)D prior to exercise. Based on these data, we conclude that pre-exercise serum 25(OH)D concentrations could influence the recovery of skeletal muscle strength after an acute bout of intense exercise.
authors.affiliation: The Orthopedic Specialty Hospital, Murray, UT 84107, USA. tyler.barker@imail.org
authors.forename: Tyler
authors.initials: T
authors.lastname: Barker
authors.forename: Vanessa T
authors.initials: VT
authors.lastname: Henriksen
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Martins
authors.forename: Harry R
authors.initials: HR
authors.lastname: Hill
authors.forename: Carl R
authors.initials: CR
authors.lastname: Kjeldsberg
authors.forename: Erik D
authors.initials: ED
authors.lastname: Schneider
authors.forename: Brian M
authors.initials: BM
authors.lastname: Dixon
authors.forename: Lindell K
authors.initials: LK
authors.lastname: Weaver
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D000704:Analysis of Variance; D001219:Aspartate Aminotransferases / Q000097:blood; D015415:Biomarkers / Q000097:blood; D015444:Exercise; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D007537:Isometric Contraction; D016014:Linear Models; D008297:Male; D018763:Muscle Fatigue; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000378:metabolism*; D020127:Recovery of Function; D012709:Serum Albumin / Q000378:metabolism; D000075462:Serum Albumin, Human; D013997:Time Factors; D014589:Utah; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: C422455:ALB protein, human; D015415:Biomarkers; C573415:IFNG protein, human; C508598:IL4 protein, human; D012709:Serum Albumin; D014807:Vitamin D; D015847:Interleukin-4; D007371:Interferon-gamma; C104450:25-hydroxyvitamin D; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D000075462:Serum Albumin, Human