Abstract
BACKGROUND: Physiotherapy protocols based on high-intensity interval training (HIIT) or eccentric hamstring exercises like Nordic Curl (NC) have been scarcely studied in futsal players. The objective of this study was to compare the effectiveness of a HIIT combined with an NC exercise program versus a HIIT-only program in futsal players. METHODS: Twenty-one futsal players were divided into (1) HIIT + NC group (n = 11, mean age = 21.55 [4.25]); and (2) HIIT group (n = 10, mean age = 20.90 [1.29]). The HIIT + NC group performed a HIIT circuit combined with 3 sets of 10 NC repetitions for 4 weeks, while the HIIT group performed the same protocol without NC exercise. Body mass index, intermittent work performance, vertical jump performance without and with arms, isometric strength of quadriceps and hamstrings, and the isometric hamstrings/quadriceps (H/Q) ratio, were assessed before and after the interventions. RESULTS: The HIIT + NC group and the HIIT group showed a significant improvement in intermittent work performance after the intervention (P = .04 and P = .01, respectively). Also, both groups showed a trend of increasing quadriceps and hamstring isometric strength, although no significant changes were found (P > .05). In addition, neither the HIIT + NC protocol nor the HIIT protocol was sufficient to yield changes in body mass index nor to improve the vertical jump performance (P > .05). CONCLUSION: Both an isolated HIIT protocol and HIIT in combination with NC exercise improved intermittent work performance in futsal players. The present study's findings may guide futsal players' physical preparation and injury prevention programs.