Research On The Changes Of Increasing Load Of Full Multi-joint Movements On The Surface EMG Of Skeletal Muscle

Objective:The paper aims to study healthy men’s each muscle dynamics and electromyography in increasing load of bench press movements and discuss the regular change to support a theory reference on Explosive Force Training, by using surface electromyography techniques, observing their speed, power of bench press during exercise and the contribution of the major muscle EMG participate in sports, as well as changes of the MF.Methods: This experimental subject for the training period is over one year in healthy men. Load mode for full flat bench press movement incremental load; increasing load levels: no load, 5kg, 10% 1RM, 20% 1RM, 30% 1RM, 40% 1RM, 50% 1RM, 60% 1RM, 70% 1RM, 80 % 1RM. Each load as fast as bench press four times between each load level rest 3-5min. Test the following indicators: measured by Keiser strength training bench press 1RM load values and levels of speed and power; through the lower surface electromyography test measured ME6000 single joint toe- deltoid, ectopectoralis, triceps, wrist ago flexors, the maximum static integral biceps EMG(i EMG) values and the increasing load bench points in each muscle EMG(i EMG) values and median frequency(MF) values, its standardized, a full flat bench press movement increasing load of the contribution of each participating muscles(bench press in a single block of muscle EMG integral part of the whole movement is divided by total points measured muscle EMG) and participation(bench press each intramuscular unit time i EMG/maximum static i EMG). Full speed exercise in healthy men increases load of muscle dynamics and the variation of each EMG. It used SPSS l9.0 statistical software.Results: 1. Bench press load and speed significant inverse relationship(P<0.05), and power is essentially parabolic relationship between the maximum power value appears in 40% 1RM-50% 1RM load point. Furthermore, 5Kg load to 10% 1RM between the actual load increases is small, but the decrease rate was large, relatively little change in its power. 2. The bench press movement in all muscles i EMG with load increments and increase levels of load growth i EMG statistically significant(P <0.05) between the load of 40% 1RM-80% 1RM. 3. Increasing load bench press of the muscle contribution, the descending order is: deltoid toe, triceps, ectopectoralis, wrist flexor, biceps, the load does not change at all levels large and the difference was not significant. 4. With the load increase, deltoid toe, triceps and pectoral muscle involvement showed a slight upward trend in basic, triceps, about half of which were significantly different between groups(P<0.05); and former wrist flexor and participation biceps little change. 5, with the load of MF incremental changes substantially following trends: little change in front deltoid, ectopectoralis first on the latter, after the first parallel decline triceps, biceps on the first post, before wrist flexor changes of muscle are U-trend. Triceps and wrist flexors before between low load and high load were significantly different(P<0.05).Conclusions: 1. In the Multi-joint participation movement, it is different between muscle and the single-joint of innervations principle, full-speed movement of each muscle fiber is not necessarily able to play its biggest strength, it is likely that the load One of the important reasons for the relationship between the resistance and the linear relationship between the speed of the show. When 40% 1RM-50% 1RM Bench is the largest and most power to achieve the best. 2. Increasing load in the bench press at full speed, with load increase i EMG increased in the number of muscle fibers to raise the number of muscle to overcome the resistance capacity is increased, but between the muscle does not vary with the size of the contribution of the load changes; 3. The full bench found in the increasing load, different muscle involvement at different load, medium load(20% 1RM-60% 1RM) exercises full of explosive action, may be more effective for improving the efficiency of the muscles acting more suitable for explosive training, low load(<20% 1RM) full of explosive exercise is more effective for the operating speed; 4.Increasing load full bench, each active muscle MF did not show decreases with decreasing speed, multi-joint participation in sports, neural regulation mechanism is different from single-joint movement, due to the multi-joint angles, muscle work When the motor unit recruitment and the dynamics of the way done with the associated action; explosive movement exercise, low load and high load can excite high frequency fast-twitch fibers.