Concentric and eccentric muscle actions and their relationship with sprint performance

The aim of the studies described in this thesis was to investigate the differences in work and metabolism between concentric and eccentric muscle actions and to examine the relationship between these muscle actions and sprint performance. The relationship between concentric and eccentric isokinetic muscle strength across three lower limb joints and sprinting performance, including the use of theoretical models was examined, in elite performers. Sprints were performed over 15 m and 35 m with times recorded over 0–15 m and 30–35 m. Using linear regression and expressing sprint performance as time, the strongest relationship found, amongst those joint actions and speeds tested, was between concentric knee extension at 240 deg.s-1 and sprint performance (0–15 m times, r=-0.518, p<0.01, and 30–35 m times, r=-0.688, p<0.01). [Continues.]