The ability to produce a timely explosive force may affect loading rate at landing

Abstract

Background Sports injuries are strongly associated with the impact loading at landing. The abilities to produce force and adjust timing are simultaneously required to absorb impact loading. Aims Hence, we aimed to examine the hypothesis that the ability to produce an explosive force at the right timing is related to the ability to absorb the impact loading at landing. Methods Twenty-nine healthy young men volunteered to participate in the study. We proposed a new test to measure the rate of force development (RFD) in accordance with the countdown signal. To evaluate the ability to produce explosive force at the right time, we measured the rate of change between the RFD at the standard start signal and the RFD at the countdown signal. Furthermore, to evaluate the ability to land from a jump, we measured the loading rate at single-leg drop landing (20 cm). Results We divided the participants into two groups based on the timing effect: the positive group (participants with increased RFD at the countdown signal, n = 11) and the negative group (participants with decreased RFD at the countdown signal, n = 18). The loading rate was significantly greater (P < .01) in the negative group (47.4 ± 11.2 body weight (BW)/s) than in the positive group (34.7 ± 7.1 BW/s). Conclusions Participants with increased RFD at the countdown signal had a lower loading rate at landing. Our results suggest that the ability to produce a timely explosive force may be a determinant of safe landing ability.

Differences in the Lateral and Vertical Jump Performances of Elite Male Basketball Players—An Axial Stabilization Training Program

“…According to research by McMahon et al, it only takes 0.1 to 0.2 s for excellent athletes to generate an explosive force from the moment that their jumping foot touches the ground to the moment that their jumping foot leaves the ground [41]. Similar studies have also pointed out that there are better RFDs that can allow for faster and more explosive movements [14,42,43].…”

“…In addition, the relationship between the RFD and explosive power will confuse players. The basis of explosive power is muscle strength, and explosive power is a manifestation of the RFD [14]. Explosive power is the ability to generate the most force in the shortest amount of time possible.…”

“…Indicators of basketball lower limb dynamics include the ground reaction force of instant take-off; the rate of force development (RFD); the time of force development; and the duration of passage height [13], which is the lower limb power calculated as the product of the vertical ground reaction force and the lower limb extension movement velocity. When the RFD of the maximum force generated by the reaction force specifically showed the value of the slope, it was found to be an important indicator of explosive power [14]. The RFD can be viewed as the slope (r) of force versus time.…”