Comparison of EMG activity in the adductors during Copenhagen adductor exercise and Adductor slide in male ice hockey players

Objectives: The aim of this study is to estimate differences in muscle activity of the adductor longus- and adductor magnus muscle during the AS with different amounts of external resistance compared to CAE in male, adult, ice hockey players. Methods: This cross-sectional study compared muscular activity (EMG) during CAE and AS in a convenience sample of male ice hockey players. The players performed AS with different external loads and EMG readings was compared to the CAE. The main outcome was differences in mean %MVIC with CAE as a reference. Differences were compared using paired t-tests and standardized effect sizes (Cohen’s d) were calculated. Results: 21 injury free male ice hockey players participated in the study. We found a statistically significant lesser muscle activation during AS compared to CAE (p<0.05), Differences in mean %MVC during concentric contractions had a range between -60% (95% CI:-82%; -37%) and -28% (-51%; -6%) for the adductor longus, and between -67% (-93%; -41%) and -36% (-53%; -19%) for the adductor magnus. Differences in mean %MVC during eccentric contractions had a range between -70% (-88%; -53%) ad -62% (-78%; -46%) for the adductor longus and between -78% (-101%; -55%) and -68% (-88%; -48%) for the adductor magnus. The effect size was moderate to high (0.45-1-85) for all differences in mean. Conclusion: The AS produces significantly less muscle activation than the CAE, concentrically and eccentrically as well as with and without external loads.