Abstract:

BACKGROUND: It is reported that the damage probability of extension muscle of the knee joint of sprint athletes is higher. Thus, it is necessary to explore the gray correlation between the inflexion muscle and extension muscle of the knee joint and the velocity of sprinters.
OBJECTIVE: To explore the correlation between strength of the knee joint and 100 m performance in sprinters using gray relational analysis.
METHODS: Biodex-Ⅱisokinetic dynamometer and rehabilitation system were applied to test the strength of the knee joint of the sprinters at low and high speed, respectively. The gray correlation between peak torque and sprint in the inflexion muscle and extension muscle of the knee joint were analyzed.
RESULTS and CONCLUISION: Under 2 speeds, the peak torque and the peak torque/weight and the peak work and the peak work/weight of the slow extension muscle were significantly greater than the fast extension muscle expect power. Simultaneously, the strength of the extension muscle was general better than the inflexion muscle. The peak torque and the peak torque/weight of the slow extension muscle and the peak torque of the slow inflexion muscle was the factor that effecting 100 m sprint performance at low speed. The peak work/weight and the peak torque/weight of the fast extension muscle of the knee joint and the peak torque/weight of the inflexion muscle was the main factor that effecting 100 m sprint performance at a high speed. The results revealed that the extension muscle strength at low speed and the inflexion muscle strength at a high speed of the knee joint are mainly factors of the sprinters.