The role of propulsive force deterioration in the deceleration phase of elite sprinting.

Objectives: The deceleration phase of sprinting is associated with a reduced capacity to produce propulsive force. This study aimed to quantify the propulsive force deterioration rate and its relationships with deceleration rate, maximum velocity (v_max), and finish velocity (v_finish) in 100 m, 200 m, and 400 m elite-level sprinters. Specifically, it aimed to quantify how differences in event-specific demands influence these relationships.

Design: Cross-sectional.

Methods: Publicly available elite-level men and women split times from 180 sprinting performances were used to estimate propulsive force deterioration rate, rate of deceleration, v_max and v_finish and other explanatory variables. These data were analysed using analysis of variance and multivariate regression to determine event-specific differences, associations and interaction effects.

Results: Increasing event distance was associated with smaller propulsive force deterioration rate, lower v_max and lower v_finish (p < 0.05). The propulsive force deterioration rate was significantly and positively associated with deceleration rate and negatively associated with vfinish in all events (p < 0.05). The propulsive force deterioration rate was also significantly and positively associated with vmax in the 200 m and 400 m events (p < 0.05) but not in the 100 m.

Conclusions: Elite-level 200 m and 400 m sprinters exhibited reduced propulsive force deterioration rates which were associated with lower v_max and greater v_finish. In the 400 m event, these results are evidence of an alternate pacing strategy perhaps to reduce energy consumption from anaerobic metabolism, whereas the 200 m results may indicate the biomechanical demands of curve running.