Prepare to fail or failing to prepare?: Acute performance after FIFA 11+ with and without strength exercises: A randomised crossover study

Background: FIFA 11+ is an injury prevention warm-up program for football that includes a strength training part. Despite its proven effectiveness in reducing injuries, uncertainty remains about whether it could impair the following performance and if it should be considered an appropriate warm-up. Few studies on the acute effects of the program have been reported, with incongruent results. Aim: To compare the acute post-exercise effects of FIFA 11+ (WU+S) and FIFA 11+ not including strength training (WU-S) on various physical performance measures. Study design: Randomised crossover study. Method: A total of 15 female junior football players completed WU+S and WU-S on separate days in randomised order. They were tested twice on each experimental session (pre-post warm-up) in isokinetic maximal voluntary contraction and countermovement jump. Sprint performance and RPE questionnaire were assessed post warm-up only. Results: Players were slower on 20 and 30 m sprint after WU+S compared with WU-S (P < 0.05), with a tendency also observed in 10 and 40 m sprint times (p < 0.06 and p < 0.052, respectively). There was a significant difference in the change in peak torque between the two groups (p < 0.05). Peak torque in the WU+S group was reduced after performing the warm-up. RPE was higher after WU+S than WU-S (p < 0.001). Conclusion: Performing the FIFA 11+ program as a warm-up routine with the strength training part impairs subsequent physical performance in female junior football players compared to performing the FIFA 11+ warm-up without the strength part.