Effects Of Pre-competition Weight Loss On Strength Quality And Physical Function Of Classical Wrestlers

Research Purpose:(1)Exploring the impact of pre-competition weight loss on strength quality and physical function of athletes.(2)This research is aiming at providing clear and intuitive trend of athletes' strength quality and physical function during the pre-competition weight loss period for coach to adjust training plan,slowing down the declining rate of strength quality to a certain degree,providing some basis for nutrition intervention during the short time before competition,making athletes maintaining good competitive level and thus achieving good results in competition.Experimental Method:(1)Experimental object: 12 athletes from Shanxi Province in preparation for 2016 National Classical Wrestling Championships.(2)Testing time: weight loss period is consisting of four weeks,the first three weeks is slow reduction period,and the forth week is rapid reduction period.The indicators used in this article are captured on every Sunday before and during the weight loss period.(3)Testing method:(1)muscle strength test: first,operator should set testing instrument to equal length mode,fix the subjects,explain the force action essentials to the subjects,and then make the subjects bent and stretch their elbows and knees for three times respectively.Each force should be increased gradually to maximum in unit time then maintained 2-3seconds and testing time interval is 3 minutes.Finally,the maximum peak strength value ofeach muscle is sorted out.(2)muscle explosive force test: first,operators should set test instrument to equal length mode,switch test system to the explosive force mode,fix the subjects,explain the essentials of the action to subjects,and then make the subjects bent and stretch their elbows and knees for three times respectively.Each force should reach the maximum value in the shortest time and testing time interval is 3 minutes.Finally,the shrinkage force-time curvature value of each muscle is sorted out.(3)body composition test:first,operators measure and record the subjects' height,age and other information,require subjects wearing high elastic clothing and pants but no jewelry,ensure subjects barefoot standing evenly on the electrode,enter the basic information of the subjects following the instruction of the body composition measurement instrument after measuring the weight,and then the subjects should press the button with two index fingers,raise their arms about 30 ° to their bodies until the end of the test.During the test,the subjects should maintain a fixed posture,and not speak or move.Finally,operators record the required indicators of this study according to the test report.(4)biochemical indicators test: Wrestling & Judo center experimenter measures required biochemical indicators using HITACHI7170 A automatic analyzer for this study and the experimental data is provided by center.Result Analysis.(1)Changes in body composition: after four weeks weight loss round,weight(6.21%?),whole-body lipid content(33.91%?)and body fat percentage(29.15%?)of classical wrestlers are significantly changed(P<0.01).Meanwhile,lean body weight(1.53%?)is changed significantly(P<0.05).(2)Changes in biochemical indicators: after four weeks weight loss round,levels of wrestler's hemoglobin and serum testosterone decrease and the differences are significant(P<0.01);Level of IgA decreases and the difference is significant(P<0.01);Level of blood urea increases and the difference is significant(P<0.01);Levels of white blood cells andserum creatine kinase increase and differences are significant(P<0.05);Other indicators have no significant changes(P>0.05).(3)Changes in strength quality:(1)muscle strength: left elbow flexor(LEF)(46.38%?),right elbow flexor(REF)(47.4%?),Left elbow extensor(LEE)(37.68%?),right elbow extensor(REE)(47.55%?),left knee flexion(LKF)(45.8%?),right knee flexion(RKF)(46%?),left knee extensor(LKE)(39.68%?),right knee extensor(RKE)(38.77%?)change significantly(P<0.01);(2)muscle explosive force: LEF(35.61%?),REF(47.2%?),LEE(41.63%?),REE(45.42%?),LKF(47.54%?),RKF(49.23%?),LKE(39.3%?),RKE(38.68%?)change significantly(P <0.01).Conclusion:(1)The weight loss method used by Shanxi Province wrestling coaches during pre-competition weight loss period can increase the consumption of fat while retaining lean body weight.(2)The immune function of the athletes is not affected during the pre-competition weight loss period.The consumption of protein decreases,the blood urea increases and blood testosterone decreases obviously in the rapid reduction period.(3)The trend of the decline strength quality of Shanxi wrestlers during the pre-competition weight loss period is mainly concentrated in the rapid reduction period.