title: Creatine supplementation does not reduce muscle damage or enhance recovery from resistance exercise.
abstract: Previous studies have shown that creatine supplementation reduces muscle damage and inflammation following running but not following high-force, eccentric exercise. Although the mechanical strain placed on muscle fibers during high-force, eccentric exercise may be too overwhelming for creatine to exert any protective effect, creatine supplementation may protect skeletal muscle stressed by a resistance training challenge that is more hypoxic in nature. The purpose of this study was to examine the effects of short-term creatine supplementation on markers of muscle damage (i.e., strength, range of motion, muscle soreness, muscle serum protein activity, C-reactive protein) to determine whether creatine supplementation offers protective effects on skeletal muscle following a hypoxic resistance exercise test. Twenty-two healthy, weight-trained men (19-27 years) ingested either creatine or a placebo for 10 days. Following 5 days of supplementation, subjects performed a squat exercise protocol (5 sets of 15-20 repetitions at 50% of 1 repetition maximum [1RM]). Assessments of creatine kinase (CK) and lactate dehydrogenase activity, high-sensitivity C-reactive protein, maximal strength, range of motion (ROM), and muscle soreness (SOR) with movement and palpation were conducted pre-exercise and during a 5-day follow up. Following the exercise test, maximal strength and ROM decreased, whereas SOR and CK increased. Creatine and placebo-supplemented subjects experienced significant decreases in maximal strength (creatine: 13.4 kg, placebo: 17.5 kg) and ROM (creatine: 2.4 degrees , placebo: 3.0 degrees ) immediately postexercise, with no difference between groups. Following the exercise test, there were significant increases in SOR with movement and palpation (p < 0.05 at 24, 48, and 72 hours postexercise), and CK activity (p < 0.05 at 24 and 48 hours postexercise), with no differences between groups at any time. These data suggest that oral creatine supplementation does not reduce skeletal muscle damage or enhance recovery following a hypoxic resistance exercise challenge.
authors: Department of Exercise Science and Athletics, Bloomsburg University, Bloomsburg, Pennsylvania 17815, USA. erawson@bloomu.edu
authors: Eric S
authors: ES
authors: Rawson
authors: Michael P
authors: MP
authors: Conti
authors: Mary P
authors: MP
authors: Miles
mesh_terms: D000328:Adult; D001265:Athletic Injuries / Q000150:complications / Q000178:diet therapy* / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D003401:Creatine / Q000008:administration & dosage*; D003402:Creatine Kinase / Q000097:blood; D019587:Dietary Supplements; D015444:Exercise / Q000502:physiology; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000293:injuries* / Q000378:metabolism; D010146:Pain / Q000209:etiology; D016059:Range of Motion, Articular; D020127:Recovery of Function; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase; D003401:Creatine