Force-velocity muscular profiles and jumping performances of soccer goalkeeper

Abstract

Summary Aims The aim of the study was to assess mechanical muscle capacities and profiles of well-trained soccer goalkeepers playing at a national amateur level. Methods Eleven goalkeepers (from 4th French division) performed vertical jump tests and series of loaded half squat and bench throw tests to assess lower and upper limbs force-velocity profiles, respectively. Force, velocity and power produced during each exercise were determined using a guided barbell. Maximal theoretical velocity and maximal theoretical force were determined from the force-velocity profiles. Slopes of those profiles were also calculated. Results Vertical jump performances were 38.5 ± 4.5 cm for the squat jump and 41.6 ± 5.5 cm for the countermovement jump. Lower limbs stiffness was 304.2 ± 55.1 N.m−1.kg−1. Lower limbs force-velocity profile was described by a slope of −11.5 ± 4.0 N.s.m−1.kg−1, with maximal theoretical force and velocity reaching 34.3 ± 5.9 N.kg−1 and 3.2 ± 0.2 m.s−1, respectively. Upper limbs muscular profile was described by a slope of −3.7 ± 1.1 N.s.m−1.kg−1, with maximal theoretical force and velocity of 13.6 ± 3.7 N.kg−1 and 3.7 ± 0.6 m.s−1, respectively. These values reveal that goalkeepers’ muscles profiles are oriented towards velocity. Conclusion This suggests that whatever the goalkeepers’ level, specific and conditioning trainings should mainly focus on velocity to optimize the performance of this specific soccer player.