Relationship between strength training and shoulder pain in male and female water polo players

The objective of this study was to assess the effect of two different strength-training methods on both male and female water polo players’ performance and shoulder pain. The players were randomly allocated to a maximum strength (MS: 14 males, 8 females) or power strength (PS: 13 males, 8 females) training group. Before and after the intervention, we assessed player´s anthropometric characteristics, shoulder internal and external rotation strength, hand grip strength, upper body strength, countermovement jump height, throwing velocity, swimming speed, shoulder pain on a visual analogue scale (VAS), wellness, and rate of perceived exertion per session. We observed no significant improvement (P< 0.05) in specific skills but enhancement in hand grip strength in male players. In female players in the MS group, throwing speed and bench press weight decreased significantly (P< 0.05). Shoulder external rotation strength at 240°/sec in male MS group players and shoulder external rotation strength at 60°/sec in female PS group players decreased significantly (P< 0.05). In addition, from the first to the last week, shoulder pain increased significantly (P< 0.05) in all players. Inverse correlations (P< 0.05) were found between VAS and shoulder rotation strength in males in the PS group, and between wellness and shoulder internal rotation strength in men in the MS group and women in the PS group. We found that both MS and PS training did not enhance performance and increased shoulder pain in male and female water polo players.