The Influence Of Different Muscle Trainings On The Muscle Strength And Its Electromyography Characteristic

Purpose: With the growing influence of sport in the world and the high techniques applied in sport studies, extensive researches have been carried out to improve the body function and physical fitness of athletes. As an effective training method, muscle contraction training got the welcome of many coaches and athletes. It exerted an important function in the daily training and the match.The aim of this paper is to assess the influence of different forms of muscle contraction training (e.g. training intensity, exercise lasting time) on the muscle contraction strength and electromyography (EMG) signal in quantitative manner. The biceps brachii of volunteers received two forms of training: the concentric contraction exercises isometric contraction exercises. Our results showed that both trainings had obvious effects on the muscle strength and muscle excitation. It indicated that the muscle strength and EMG indexes could be altered under isometric contraction exercises as well as concentric contraction exercises.Methods: The 16 healthy male volunteer athletes were divided into two teams, No1 and No2. Eight volunteers in No1 team were required to take part in concentric contraction exercises, while the other eight volunteers in the No2 team received isometric contraction trainings.The No.1 team was divided into four sub-groups. The first group took warm-up exercise for twelve times by using 40% of the maximal contraction strength. The other three groups exercised by using 70% of the maximal strength for eight times. Interval time of each exercise was one minute.The No.2 team was also divided into four sub-groups. The first group took warm-up exercise with 60% of the maximal contraction strength. The other three groups exercised with 90% of the maximal strength for 35 seconds in each group. The angle of elbow joint was kept 90 degrees during exercises. Interval time of each exercise was one minute.All trainings were carried on for 4 weeks with 3 times every week. The value of maximal contraction strength, IEMG and RMS of biceps brachii were determined from electromyography (EMG) analysis by using EMG instrument (Keypoint Lite-II) . Data from volunteers before and after the trainings was compared by using cultural heritage data method, experimental method, mathematical statistics method respectively.Results: (1) There was significant difference in maximal strength of muscle between before and after exercises in either concentric contraction training team or isometric contraction one (P<0.01). It indicated that the maximal strength of muscle was enhanced through four-week muscle contraction training.(2) A significant difference in IEMG value of muscle was observed between before and after exercises in either concentric contraction training team or isometric contraction one (P<0.05). It showed that IEMG value of muscle could increase with the four-week muscle contraction training.(3) RMS value of muscle was also significantly different in either concentric contraction training team or isometric contraction one between before and after exercises (P<0.05). It indicated that RMS value of muscle could increase with the four-week muscle contraction trainings .Conclusion(1) Both concentric contraction and isometric contraction trainings remarkably enhanced the muscle strength of volunteer athletes. The concentric contraction training was better than isometric contraction training in enhancing the strength of biceps brachii.(2) IEMG value of muscle increased remarkably after concentric contraction and isometric contraction trainings. The concentric contraction training was better compared with isometric contraction training in the IEMG value increase of biceps brachii.(3) RMS value of muscle increased remarkably after concentric contraction and isometric contraction trainings. The concentric contraction training was better than isometric contraction training in the RMS value increase of biceps brachii.(4) Isometric contraction training had a certain effect on enhancing the strength of muscle. However, duration of training time, how to make reasonable use of the EMG in the muscle strength study and the how to combine the isometric contraction training with common muscle strength training, could be considered in the further research.