TY - JOUR T1 - Copenhagen adduction exercise can increase eccentric strength and mitigate the risk of groin problems: but how much is enough! JF - British Journal of Sports Medicine JO - Br J Sports Med DO - 10.1136/bjsports-2020-103564 SP - bjsports-2020-103564 AU - Lasse Ishøi AU - Kristian Thorborg Y1 - 2021/02/24 UR - http://bjsm.bmj.com/content/early/2021/02/23/bjsports-2020-103564.abstract N2 - Low eccentric hip adduction strength increases the risk of hip adductor injury in football and ice hockey,1 2 emphasising the role of implementing strategies to target this. The Copenhagen Adduction exercise3 (video: www.youtube.com/watch?v=L6qfTLKhjnk) has achieved popularity in the sports medicine community. The exercise can be performed at pitch side without equipment,3 and elicits high muscle activity in the adductor longus3 and large eccentric hip adduction strength gains.4 These attributes facilitated the trial by Haroy et al; a prevention study that reported a 41% reduction of groin problems in football players following a Copenhagen Adduction exercise intervention initiated in the pre-season and maintained in the in-season.5 While bodyweight exercises, such as the Copenhagen Adduction exercise, are feasible for on-field implementation, such exercises have traditionally been questioned by exercise scientists and specialist in terms of their ability to elicit large strength gains, as progression relies mainly on adding more repetitions, rather that increasing exercise intensity.6 However, since the number of repetitions is the most clinically applicable progression variable for the Copenhagen Adduction exercise, understanding how this associates with improvements in hip adduction strength is important when prescribing the exercise for risk mitigation. Therefore, the purpose of this editorial is to analyse and discuss the role of training volume (number of repetitions and time under tension) as a simple progression principle to elicit eccentric hip adduction … ER -