Effects of the FIFA 11+ on ankle evertors latency time and knee muscle strength in amateur futsal players.

Background: The FIFA 11+ has shown to increase muscle strength and reduce injury risk. The purpose of this study was to assess the short and long-term effects of the FIFA 11+ on knee strength, and muscle latency after sudden inversion of amateur futsal players.Methods: Seventy-one male futsal players were recruited and randomized to a FIFA 11+ (n = 37, age: 27.0 ± 5.1 years) and a control group (n = 34, age: 26.0 ± 5.1 years). The FIFA 11+ programme was executed twice a week, for 10 weeks, followed-up after 10 weeks where both groups executed regular warm-ups. Concentric and eccentric isokinetic knee muscle strength was tested and latency time of the evertor muscles after sudden inversion of the ankle was executed with a trapdoor mechanism following an EMG protocol of selected leg muscles (peroneus brevis and peroneus longus).Results: No significant difference were observed between groups for short-term changes in isokinetic strength after adjustment for baseline differences. At long-term, significant gains were obtained after adjustment for baseline differences in eccentric strength for both lower limbs as for the H/Q ratios for the dominant limb. No changes between groups were observed in the peroneus brevis and peroneus longus latency time.Conclusions: Performing FIFA 11+ did not have short-term effects on knee strength and muscle latency after sudden inversion in amateur futsal players. However, significant long-term benefits were observed for eccentric strength and H/Q ratios.