Author(s): JIE, Z., YING, Z., RURU, Z., LANJUAN, L., NIELS, B.J.V., DANIEL, K., MATTHEW, H., Institution: DONGHUA UNIVERSITY;UNIVERSITY OF STIRLING, Country: UNITED KINGDOM, Abstract-ID: 564

INTRODUCTION:
Elastic band resistance training (EBRT) is beneficial for improving the specific strengths of sprinters(1). However, it is not clear whether the mode and working characteristics of the swinging leg muscle exertion while using swing technique are consistent with those during actual sprint performance. To achieve the optimal training effect, those specific strengths must be trained by using training methods that are specific to, and meet, or exceed the requirements of competitive contexts(2). In other words, the training effect of those specific strengths can be greatly affected by training regimens including motion range, movement speed, muscle exertion characteristics, working mode, and the extent to which the energy supply systems adapt to the requirements of specific movements and techniques(3). Therefore, the study aimed to use the synchronous testing methods of kinematics and sEMG to test the swing technique action in maximum sprint running(MSR) and the swing technique during the EBRT for Chinese elite sprinters. In addition, the study also explored the muscle sEMG characteristics of the swing leg in these athletes’ response to sprint performance and specific strength training.
METHODS:
Surface electromyography telemetry technology and high-speed camera were used to simultaneously test kinematics and muscle exertion characteristics of lower limb swing technique in high-level sprinters during EBRTand MSR.
RESULTS:
The angle changes response to swing technique showed a significant difference in Maximum value of thigh angle(EBRT:183 ± 4,MSR:161±6,Deg;p=0.000), thigh flexion range(EBRT:160±9,MSR:99±6,Deg;p=0.000), and minimum value of knee angle(EBRT:40 ± 11, MSR: 30 ± 3, Deg;p=0.048) between EBRT and MSR . However, no significant difference was shown in the values for knee flexion range(EBRT:110 ± 22,MSR :122 ±7,Deg;p=0.186). The angular velocity changes response to swing technique showed a significant higher for maximum value of thigh flexion angular velocity in EBRT than MSR (EBRT:1069 ± 168, MSR: 828 ±72 , deg•s-1;p=0.016).
When completing EBRT and MSR swing technique, each muscle group of the swing leg show distinct temporal sequence. The standardized mean value of Average EMG (AEMG) of FL(p=0.000) and SEM(P= 0.008 )were shown in significant difference between EBRT and MSR.there was a significant difference in AEMG of RF(p=0.087), GM(p=0.012) ,TA(p=0.472) between EBRT and MSR . No significant difference was shown in AEMG of VMO(p=0.080),VLO(p=0.055),BF(p=0.187), Ta(p=0.472),LG(P=0.562) between EBRT and MSR.
CONCLUSION:
In the practice of special strength training for sprinting running, we should know EBRT could effectively develop thigh forward swing speed and develop the special strength of single muscle groups such as RFandTA; however, the leg muscle activity sequence and muscle group coordination were not consistent with MSR swing technique. This may affect the training effect of the specific strengths of lower limb swing technique for optimal sprint performance.