Acute adaptation to low volume eccentric exercise.
OBJECTIVE
Many symptoms of eccentric muscle damage can be substantially reduced if a similar eccentric bout is repeated within several weeks of the initial bout. The purpose of this study was to determine whether a nondamaging, low repetition, low volume eccentric exercise bout could also provide a protective/adaptive effect.


METHODS
Subjects were assigned to a control (CON), eccentric exercise (ECC), or low volume familiarized eccentric exercise group (LV+ECC). Before the study, the LV+ECC group performed six maximal eccentric contractions during two familiarization sessions. The main eccentric bout targeted the elbow flexor muscle group and consisted of 36 maximal eccentric contractions. Muscle soreness, upper arm girth, elbow angle, creatine kinase activity, isometric torque, and concentric and eccentric torque at 0.52 and 3.14 rad.s-1 were assessed 0, 1, 2, 3, 4, 7, and 10 d postexercise.


RESULTS
No evidence of muscle damage was observed as a result of the low volume eccentric bouts. Nevertheless, with the exception of muscle soreness and concentric torque, all variables recovered more rapidly in the LV+ECC group (P < 0.05).


CONCLUSIONS
Adaptation to eccentric exercise can occur in the absence of significant muscle damage. Exposure to a small number of nondamaging eccentric contractions can significantly improve recovery after a subsequent damaging eccentric bout. Furthermore, this adaptation appears to be mode-specific and not applicable to concentric contractions.
Paddon-Jones
D
D
School of Human Movement Studies, The University of Queensland, Brisbane, Queensland, 4072, Australia. djpaddon@utmb.edu
Abernethy
P J
PJ
D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D001132:Arm / Q000502:physiology; D003402:Creatine Kinase / Q000097:blood; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000293:injuries* / Q000503:physiopathology*; D010146:Pain / Q000209:etiology; D019415:Torque
D003402:Creatine Kinase