Creatine or vitamin D supplementation in individuals with a spinal cord injury undergoing resistance training: A double-blinded, randomized pilot trial

Purpose: Determine whether creatine or vitamin D supplementation improves muscle strength in individuals with spinal cord injury undergoing resistance training.Methods: Thirteen male and one female with spinal cord injury, from two Portuguese rehabilitation centers, were randomized to creatine (3g daily), vitamin D (25000 IU each two weeks) or placebo group in a double-blind design. All participants performed progressive resistance training during eight weeks. The outcome measures, obtained at baseline and after intervention, included: Sum of four skinfolds; Corrected arm muscle area; Seated medicine ball throw; Handgrip strength with dynamometer; Manual wheelchair slalom test and one repetition maximum for Chest press, Triceps, Pec deck and Lat pulldown. Vitamin D levels were obtained in all participants before and after intervention.Results: 71.4% of participants had deficit values of vitamin D. The corrected arm muscle area improved significantly (p<0.05) in creatine group relatively to the control gro...