Abstract:

BACKGROUND: There is a lack of large-sampled comparative study on the kinematics and surface electromyography (sEMG) between elite and general hand ring athletes undergoing cross bracing.
OBJECTIVE: To explore the time and angle of cross support and the sEMG of main muscle groups in elite hand ring athletes, and to compare the differences between elite and general athletes.
METHODS: Two high-speed cameras and MegawinT8 sEMG analyzer were used to collect the measurements in elite group (n=13, elite and first-level athletes) and general group (n=14, second-level athletes). The kinematics (time and angle) of positive/inverted/horizontal cross support and sEMG of trapezius, latissimus dorsi, teres major, deltoid, triceps brachii, pectoralis major, serratus anterior and biceps brachii were detected.
RESULTS AND CONCLUSION: Compared with the general group, in the elite group, the positive cross support time increased by 58.9% (P < 0.01), left and right elbow angle was increased by 16.4% and 17.3% (P < 0.05), the angle between the left and right shoulder line and a horizontal surface was decreased by 46.9% and 49.2% (P < 0.01). The contribution rate of latissimus dorsi, teres major, and deltoid was increased by 28.8%, 108.1% (P < 0.01) and 5.8% (P < 0.05), respectively. The contribution rate of triceps brachii, pectoralis major, and biceps brachii was decreased by 47.8% (P < 0.01), 16.2% and 16.7% (P < 0.05). Compared with the general group, in the elite group, the inverted cross support time was increased by 81.6% (P < 0.01). The contribution rate of trapezius, teres major and triceps brachii was increased by 25.6%, 128.6% and 175.0% (P < 0.01), respectively. The contribution rate of serratus anterior and biceps brachii was reduced by 17.9% and 20.7% (P < 0.01). The horizontal cross support time, hip and knee angles were increased by 59.9% (P < 0.01), 9.0% and 6.9% (P < 0.05). The left and right wrist shoulder angles, and trunk angle was decreased by 20.4%, 22.1% and 31.1% (P < 0.01). The contribution rate of trapezius, latissimus dorsi and teres major was increased by 14.0% (P < 0.05), 508.3% and 18.2% (P < 0.01). The contribution rate of anterior serratus was decreased by 12.5% (P < 0.05). These findings indicate that control of the cross support time and the angle of the body position, and strengthening the participation degree and control ability of the latissimus dorsi, trapezius, triceps, musculus and deltoid contribute to completing the hand ring better.

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程

Key words: Sports Medicine, Electromyography, Muscles, Tissue Engineering