The effect of the bend on technique and performance during maximal effort sprinting

Abstract

This study investigated changes in performance and technique that occur during maximal effort bend sprinting compared with straight-line sprinting under typical outdoor track conditions. Utilising a repeated measures design, three-dimensional video analysis was conducted on seven male sprinters in both conditions (bend radius: 37.72 m). Mean race velocity decreased from 9.86 to 9.39 m/s for the left step (p = 0.008) and from 9.80 to 9.33 m/s for the right step (p = 0.004) on the bend compared with the straight, a 4.7% decrease for both steps. This was mainly due to a 0.11 Hz (p = 0.022) decrease in step frequency for the left step and a 0.10 m (p = 0.005) reduction in race step length for the right step. The left hip was 4.0° (p = 0.049) more adducted at touchdown on the bend than the straight. Furthermore, the bend elicited significant differences between left and right steps in a number of variables including ground contact time, touchdown distance and hip flexion/extension and abduction/adduction angles. The results indicate that the roles of the left and right steps may be functionally different during bend sprinting. This specificity should be considered when designing training programmes.

Force production during maximal effort bend sprinting: Theory vs reality

“…They suggested that swing time would remain constant and, therefore, step frequency would decrease. The increased left step ground contact time in the present study is in line with previously reported increases of 11 ms in left step ground contact time during maximal effort bend sprinting (Churchill et al., ). Alt et al.…”

“…On the other hand, Churchill et al. () reported that the right hip abduction/adduction angle at touchdown was not significantly affected by the bend and that peak adduction was less on the bend compared with the straight. The inward lean and abduction/adduction angles could also influence why there were statistically significant differences in horizontal braking impulses between left and right step on the bend (left step braking larger) and between the straight and bend conditions for the left leg (bend condition larger).…”

“…Kinematic analysis of maximal (Churchill et al., ) and submaximal (Alt et al., ) effort bend sprinting has shown that inward lean during bend sprinting results in greater adduction of the left hip during the ground contact phase of bend sprinting compared with straight‐line sprinting. On the other hand, Churchill et al.…”

“…(). The mass of a typical spiked sprinting shoe (0.2 kg; Hunter et al., ) was added to the mass of each foot with 85% and 15% added to the rearfeet and forefeet, respectively (Churchill et al., ). The ratios of the total mass for all segment masses were, thus, adjusted accordingly.…”

“…Churchill et al. () reported that, during maximal effort sprinting on a track bend radius of 37.72 m, more turning was achieved during the left ground contact than the right. This suggests that when sprinting maximally at radii typical of an athletics track, the left leg may produce greater inward force than the right leg.…”