title: Kinematic adaptations in sprint acceleration performances without and with the constraint of holding a field hockey stick.
abstract: The aim of this study was to investigate the technique adaptations made when performing sprint-based tasks without (free condition) and with (constrained condition) the constraints of carrying a field hockey stick. Three free and three constrained maximal sprint accelerations were performed by 18 experienced university male field hockey players (age = 20 +/- 1 years, body mass = 73.3 +/- 7.1 kg, and stature = 1.78 +/- 0.05 m). An automatic motion analysis system tracked sagittal plane active marker locations (200 Hz). M sprint velocity during the 18-22 m (free: 8.03 +/- 0.43 m/s; constrained: 7.93 +/- 0.36 m/s) interval was significantly (p = 0.03) different between free and constrained conditions. While the M stride length and stride frequency was similar between free and constrained conditions in the 2-13 m capture volume, the free condition elicited a 0.10 m/s faster (p = 0.03) stride velocity. Further significant differences were found between free and constrained kinematic profiles (p < or = 0.05) for the hip angular velocity at touchdown during the 2-12 m interval of the sprints and in the overall sprint technique coordination between free and constrained conditions. Performance and technique adaptations indicated that sprint-training protocols for field sports should integrate specific equipment constraints to ensure explicit replication of the mechanical demands of the skills underpinning superior performance.
authors.affiliation: Cardiff School of Sport, Cardiff Metropolitan University, Cardiff, UK. mawdowski@cardiffmet.ac.uk
authors.forename: Maximilian M
authors.initials: MM
authors.lastname: Wdowski
authors.forename: Marianne J R
authors.initials: MJ
authors.lastname: Gittoes
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D001696:Biomechanical Phenomena / Q000502:physiology; D016001:Confidence Intervals; D006621:Hip Joint / Q000502:physiology; D006688:Hockey / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D035002:Lower Extremity / Q000502:physiology*; D008297:Male; D012420:Running / Q000502:physiology*; D018709:Statistics, Nonparametric; D055815:Young Adult