An Experimental Study On The Effect Of Lower Limb Complex Training On Volleyball Players’ Jumping Ability

Objective: With the increase of training years and the gradual adaptation to load stimulation intensity,the training effect will gradually appear ’saturation’ state,especially the growth of strength and bounce ability will also appear ’bottleneck’ phenomenon.In order to explore a more effective method,this study intends to through the intervention ’s squat + continuous jump’ mode,the university high level volleyball players bounce ability of experimental research,to verify the training effect and explore its mechanism.Methods: The high-level male volleyball players in Yanshan University were selected as the experimental subjects.The subjects were divided into experimental group and control group by the method of complex training of lower limbs.The experimental group was given complex training,and the control group was given traditional resistance training.The experimental test was divided into two parts.The first part was to monitor the EMG indexes of the two training methods in the intervention process,which was used to compare the differences in the working principle of the muscles in the training process of the two methods.The other part was the pretest and posttest of the intervention experiment.The kinematics,dynamics and EMG indexes of the in-situ longitudinal jump and run-up take-off were tested.Compare the training effect of the two training methods.Results:(1)After 8 weeks of intervention training,the experimental group in situ vertical jump increased by 5.46 cm,run-up jump increased by 3.38 cm;compared with the control grou p,the scores of in-situ vertical jump and run-up take-off were significantly improved(P <0.05).(2)After 8 weeks of intervention training,the original vertical jump stretching time of the experimental group was reduced by 0.015 s,and the run-up jumping stretching time w as reduced by 0.016 s.Compared with the control group,the original vertical jump stretchi ng time was significantly reduced(P < 0.05);in the experimental group,the buffer time of in situ vertical jump was reduced by 0.015 s,and the buffer time of run-up jump was re duced by 0.01 s.Compared with the control group,the buffer time of in situ vertical jump was significantly reduced(P < 0.05).Experimental group in situ vertical jump flight time increased 0.088 s;experimental group run-up jump time increased 0.045 s;compared wi th the control group,the take-off time of in-situ longitudinal jump and run-up jump was si gnificantly increased(P < 0.05).(3)After 8 weeks of intervention training,the horizontal squat 1RM values of the two groups were significantly improved(P < 0.05),and the experimental group increased by7.5 kg.Compared with the control group,the improvement was significantly better than th at of the control group(P < 0.05).(4)In the centrifugal stage,the muscle contribution rate of lateral femoral muscle,me dial femoral muscle and tibialis anterior muscle was significantly higher than that of deep j ump,and the muscle contribution rate of biceps femoris,lateral head of gastrocnemius and medial head of gastrocnemius was significantly lower than that of deep jump.At the centr ipetal stage,the muscle contribution rates of lateral thigh muscle and anterior tibial muscle at barbell level were significantly higher than those at jump depth,and the muscle contrib ution rates of lateral gastrocnemius head and medial gastrocnemius head were significantl y lower than those at jump depth.(5)In the centrifugal stage,the RMS values of the lateral femoral muscle and tibial a nterior muscle of the barbell horizontal squat were significantly greater than those of the ju mp depth(P < 0.05),and the RMS values of the biceps femoris,the lateral head of gastro cnemius and the internal probe of gastrocnemius were significantly smaller than those of t he jump depth(P < 0.05).At the centripetal stage,the RMS value of the rectus femoris w ith horizontal barbell squat was significantly higher than that of the jump depth(P < 0.05),and the RMS values of the biceps femoris,anterior tibial muscle,lateral head of gastroc nemius muscle and internal probe of gastrocnemius muscle were significantly lower than t hose of the jump depth(P < 0.05).Conclusions :(1)After eight weeks of intervention training,the compound training can more effectively shorten the time of stretching and buffering in the process of vertical jump than the barbell horizontal squat training,which has a significant effect on improving the explosive force and lower limb strength of volleyball players.(2)The effect of barbell horizontal squat training on the anterior thigh muscles is more prominent,and the effect of compound training on the large and calf muscles is relatively more comprehensive and balanced.Especially,the effect on calf muscle group and biceps femoris is more prominent.(3)The contribution ratio of deep jump training and longitudinal jump to the monitoring of muscle groups is close,and it is more similar in the mode of action and the principle of muscle work.