Abstract
Hazardous knee biomechanics, such as excessive knee affordance link with injuries in volleyball spike jumps (SPJs) and can be reconfigured by the enhancement of internal focus. The study aimed to explore the effects of video tasks illustrating a high-level SPJ on knee movement in the volleyball SPJ with 15 elite male volleyball athletes. This study investigated the knee movements in sagittal, coronal, and transverse planes before and after the video task in SPJ using one-dimensional statistical parametric mapping (SPM 1D) and discrete statistics. The SPM 1D indicated a larger knee flexion angle (31.17–73.19%, t = 2.611, and p = 0.012), increased knee flexion moment (19.72–21.38%, t = 0.029, and p = 0.029), and increased knee adduction angular velocity (49.07–62.64%, t = 3.148, and p = 0.004) after video task; alternatively, smaller knee external rotation angular velocity (45.85–49.96%, t = 5.199, and p = 0.017) and vertical ground reaction (vGRF) (3.13–5.94%, t = 4.096, and p = 0.014; 19.83–21.97%, t = 4.096, and p = 0.024) were found after the task. With discrete value statistics, the video task increased the peak of knee flexion angle while decreased the peak of extension moment, flexion moment, abduction moment, external moment, the first peak vGRF, and related loading rate.Conclusions: The results indicate that knee biomechanics in volleyball SPJ positively influenced by the video task. The task has the athletes control the knee movements more actively and improves the original hazardous movement strategies. Therefore, the video task presumably can abate the occurrence of knee injuries in volleyball SPJ. Further validation especially in the exercise effect is needed in the future.
Highlights
Volleyball is a popular Olympic sport wherein athletes have to perform complex actions
The objective of this research was to determine the effect of video tasks on knee movements during volleyball spike jumps (SPJs) in male athletes
The decrease in the first peak of vGRF along with the near region (3.13–5.94%) and its loading rate after the instructions directing attention internally reported in this study is presumably because body segments are affected more by the internal focus according to a previous study (Vance et al, 2004)
Summary
Volleyball is a popular Olympic sport wherein athletes have to perform complex actions. Spike jumps (SPJs) are the necessary skills in determining match results in volleyball (Costa et al, 2017). The SPJ movement, such as run-up and braking before take-off (Coleman et al, 1993). Research has indicated that sports, such as cutting, stop-jump, landing, or sudden deceleration are commonly related to acute knee injuries (Coleman et al, 1993; Zahradnik et al, 2015; Yang et al, 2018; Mohd Azhar et al, 2019). Further research on the training program for knee injury prevention is needed
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call