title: A light load eccentric exercise confers protection against a subsequent bout of more demanding eccentric exercise.
abstract: This study investigated the hypothesis that a light eccentric exercise (ECC) that does not induce a loss of muscle function and delayed onset muscle soreness would confer a protective effect against a more strenuous ECC. Eighteen young men were randomly placed into two groups: 10-40% (n=9) and 40% (n=9). Subjects in the 10-40% group performed ECC of the elbow flexors (six sets of five reps) using a dumbbell set at 10% of maximal isometric strength (MVC) at an elbow joint angle of 90 degrees , followed 2 days later by ECC using a dumbbell weight of 40% MVC. Subjects in the 40% group performed the 40% ECC only. Changes in MVC, range of motion (ROM), upper arm circumference (CIR), plasma creatine kinase (CK) activity and muscle soreness before, immediately after, 1-5 and 7 days following the 40% ECC were compared between groups by a two-way repeated measures ANOVA. No significant changes in any of the criterion measures were found immediately and 1-2 days after the 10% ECC. Following the 40% ECC, the 10-40% group showed significantly (P<0.05) smaller decreases in MVC and ROM, and smaller increases in muscle soreness compared with the 40% group, but no significant differences between groups were evident for CIR and plasma CK activity. These results suggest that the 10% ECC induced some protection against a subsequent bout of 40% ECC performed 2 days later. It appears that the light eccentric exercise preconditioned the muscles for exposure to the subsequent damaging eccentric exercise bout.
authors: Graduate School of Integrated Science, Yokohama City University, Yokohama, Japan.
authors: Andrew P
authors: AP
authors: Lavender
authors: Kazunori
authors: K
authors: Nosaka
mesh_terms: D000293:Adolescent; D000328:Adult; D001265:Athletic Injuries / Q000503:physiopathology / Q000517:prevention & control*; D015444:Exercise / Q000502:physiology; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000293:injuries* / Q000503:physiopathology; D010806:Physical Education and Training / Q000379:methods*; D010807:Physical Endurance / Q000502:physiology*; D034941:Upper Extremity / Q000293:injuries / Q000502:physiology; D014891:Weight Lifting / Q000502:physiology*