Do dominant and non-dominant arms respond similarly to maximal eccentric exercise of the elbow flexors?
OBJECTIVE
Two common models to investigate the effect of interventions on muscle damage include using two groups in which one group receives an intervention while the other acts as control, and using contralateral limbs of one group. The latter model is based on the assumption that changes in markers of muscle damage are similar between limbs, but this has not been examined systematically.


METHODS
This study compared changes in muscle damage markers between dominant and non-dominant arms following maximal eccentric exercise of the elbow flexors.


METHODS
Eighteen men performed 60 maximal eccentric elbow flexions of each arm separated by 4 weeks with the order of testing between arms randomised. Maximal voluntary isometric torque, range of motion, upper arm circumference, plasma creatine kinase (CK) activity and muscle soreness before and for 7 days following exercise were compared between arms using two-way repeated measures ANOVA.


RESULTS
No significant differences between arms were evident for any of the markers, but significant (P<0.05) differences between first and second bouts were evident for changes in strength, circumference and CK with smaller changes following the second bout. A poor correlation was found for the magnitude of changes in the markers between dominant and non-dominant arms, suggesting that responses to eccentric exercise were not necessarily the same between arms.


CONCLUSIONS
These results show that the order affected the responses of dominant and non-dominant arms to the eccentric exercise; however, the contralateral limb design appears to be usable if bout order is counterbalanced and randomised among participants.
School of Exercise and Health Sciences, Edith Cowan University, Western Australia, Joondalup, Western Australia.
Michael J
MJ
Newton
Paul
P
Sacco
Dale
D
Chapman
Kazunori
K
Nosaka
D000328:Adult; D001132:Arm / Q000502:physiology*; D015415:Biomarkers / Q000097:blood; D003402:Creatine Kinase / Q000097:blood*; D004550:Elbow / Q000502:physiology*; D004551:Elbow Joint / Q000502:physiology; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D059352:Musculoskeletal Pain / Q000097:blood / Q000209:etiology / Q000503:physiopathology; D055070:Resistance Training; D019415:Torque
D015415:Biomarkers; D003402:Creatine Kinase