Oral creatine supplementation enhances upper extremity work capacity in persons with cervical-level spinal cord injury.

Abstract

To examine the effects of short-term creatine monohydrate supplementation on the upper extremity work capacity of persons with cervical-level spinal cord injury (SCI). Randomized, double-blind, placebo-controlled, crossover design study. Consists of 2 treatment phases lasting for 7 days, separated by a 21-day washout period. University research laboratory trial. Sixteen men with complete cervical-level SCI (C5-7). Subjects were randomly assigned to 1 of 2 groups and received either 20g/d of creatine monohydrate supplement powder or placebo maltodextrin powder for the first treatment phase; the treatment was reversed in the second phase. Incremental peak arm ergometry tests, using 2-minute work stages and 1-minute recovery periods, were performed immediately before and after each treatment phase (total of 4 assessments). The initial stage was performed unloaded, with power output progressively increased 10 watts/stage until subjects had achieved volitional exhaustion. Peak power output, time to fatigue, heart rate, and metabolic measurements, including oxygen uptake (VO2), minute ventilation, tidal volume (VT), and respiration frequency. Significantly greater values of VO2, VCO2, and VT at peak effort after creatine supplementation (P <.001). Creatine supplementation enhances the exercise capacity in persons with complete cervical-level SCI and may promote greater exercise training benefits.