Influence of the Intention to Lean the Body Forward on Kinematics and Kinetics of Sprinting for Active Adults

Abstract

This study investigated the influence of the intention to lean the body forward on spatiotemporal and ground reaction force variables during the acceleration phase of a sprint. Fourteen active adults performed two 50 m sprints (with and without the intention to lean), during which spatiotemporal variables and impulses were obtained using a long force platform system. Effect size (Cohen’s d) was used to examine the differences between the two trials. We found that running speed and net anteroposterior impulse did not change by the intention for all steps. However, step frequency increased in the initial two steps through decreases in support time and flight time by the intention. Moreover, these shorter support and flight times were caused by a decrease in the vertical impulse. The propulsive impulse did not change during the initial part of acceleration phase, but the braking impulse decreased at the first step. This study demonstrates that an intention to lean the body forward leads to a smaller braking impulse and a higher step frequency through shorter support and flight times and a smaller vertical impulse during the initial part of the acceleration phase of a sprint.

Comparison of development of step-kinematics of assisted 60 m sprints with different pulling forces between experienced male and female sprinters

“…The assisted load had most influence after 15% of the distance (after 9 m) as no significant differences in kinematics were observed in earlier phases. This was probably caused by the positioning of the athletes as they leaned forwards for producing maximal horizontal forces [1,31,32], without breaking the steps. That it occurred from this point on (after 15% of distance) is in accordance with the "first transition" during the acceleration phase when sprinting [28][29][30].…”

The correlation of endurance and speed on the performance of Long-Distance Runners 2022 in East Java Province

“…Strength training for leg muscles and abdominal muscles in adolescents is related to cardiorespiratory endurance (Moseset al, 2023). The two variables can also predict marathon performance, body fat percentage, and recovery heart rate (Kenneallyet al, 2021).lean the body forward running produces consistent acceleration performance (Nagahara et al, 2019) .Page 439 / 444.…”