Alterations to the orientation of the ground reaction force vector affect sprint acceleration performance in team sports athletes. Issue 18 (17th September 2017)

• Record Type: Journal Article
• Authors: Bezodis, Neil E.; North, Jamie S.; Razavet, Jane L.
• Is Part Of: Journal of sports sciences. Volume 35:Issue 18(2017)
• Page Start: 1817
• Page End: 1824
• Publication Date: 2017-09-17
• Subjects: Attentional focus -- biomechanics -- ratio of forces -- sprinting -- technique; Sports -- Periodicals; Sports -- Physiological aspects -- Periodicals; Sports -- Psychological aspects -- Periodicals; 612.044
• DOI: 10.1080/02640414.2016.1239024
• Languages: English
• ISSNs: 0264-0414

Abstract

ABSTRACT: A more horizontally oriented ground reaction force vector is related to higher levels of sprint acceleration performance across a range of athletes. However, the effects of acute experimental alterations to the force vector orientation within athletes are unknown. Fifteen male team sports athletes completed maximal effort 10-m accelerations in three conditions following different verbal instructions intended to manipulate the force vector orientation. Ground reaction forces (GRFs) were collected from the step nearest 5-m and stance leg kinematics at touchdown were also analysed to understand specific kinematic features of touchdown technique which may influence the consequent force vector orientation. Magnitude-based inferences were used to compare findings between conditions. There was a likely more horizontally oriented ground reaction force vector and a likely lower peak vertical force in the control condition compared with the experimental conditions. 10-m sprint time was very likely quickest in the control condition which confirmed the importance of force vector orientation for acceleration performance on a within-athlete basis. The stance leg kinematics revealed that a more horizontally oriented force vector during stance was preceded at touchdown by a likely more dorsiflexed ankle, a likely more flexed knee, and a possibly or likely greater hip extension velocity.