Measuring eccentric hip adductor strength during the Copenhagen adduction exercise: A proof-of-concept and test re-test reliability study

To describe a novel method for measuring eccentric hip adductor (EHAD) strength during the Copenhagen adduction exercise (CAE) and investigate the test re-test reliability of this measure. Test re-test reliability study. Twenty male athletes aged 24±6 years participated in two data collection sessions 7±2 days apart. During each data collection session, participants performed three maximal effort repetitions of the CAE with their leg supported by an ankle strap hung from a fixed barbell. We attached a commercially available load cell in-series with the ankle strap to measure peak force in Newtons (N) during the eccentric lowering phase of the CAE. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), SEM as a percentage of the mean (SEM%) and minimal detectable change at a 95% confidence interval (MDC 95 ) were calculated for this measure of EHAD strength. Test re-test reliability was good for EHAD strength measured during the CAE on dominant (ICC = 0.84; SEM% = 3.6%; MDC 95 = 33 N) and non-dominant (ICC = 0.87; SEM% = 3.3%; MDC 95 = 29 N) legs. This study provides proof-of-concept that EHAD strength can be measured during the CAE with good test re-test reliability. • We describe a new method for measuring eccentric hip adductor (EHAD) strength • We measured EHAD strength during the Copenhagen adduction exercise (CAE) • Equipment used to measure EHAD strength during the CAE was relatively inexpensive • Test re-test reliability was good for this new method in male athletes