The Sports Biomechanical Analysis Of Sanda Whipping-kick

Objective:Given the importance of whipping-kick techniques in Sanda and the lack ofresearch on sports biomechanics. In order to study the technical characteristics ofwhipping-kick action in Sanda better; combat effects; endurance characteristics ofspecific strength, speed, endurance, and joint muscle strength characteristics;neuromuscular activity characteristics; kinematic characteristics; dynamiccharacteristics; in order to promote and develop Wushu Sanda exercise and explorethe similarities and differences of Sanda athletes at different levels; providingevidences and theories for scientific training about Sanda. This article will use themultifunctional force targets, isokinetic dynamometry, action analysis ofelectromyogram telemetry systems, wireless systems, and a three dimensionalmeasuring instruments of experimental study on different of Sanda athletes whip-kicktechnique at sports levels. Using biomechanical knowledge to study the technicalcharacteristics of the whip leg movement in Sanda, neuromuscular characteristics andspecial forces combat effectiveness, providing rationale and data support for scientifictraining in Sanda.Research methods:Subject: According to Sanda campaign levels, we divide it into outstandinggroup and common group, each group has13athletes.Experimental instruments: VIVON motion analysis system, Noraxon system,wireless EMG test system, Kistler three-dimensional force platform, dynamometerstation synchronization signal of Noraxon, force measurement target, BIODEXisokinetic testing system.Experimental program: the entire experimental test is divided into three parts:VICON, Wireless EMG,3-D force platform, synchronous test of force measuringtarget;30seconds continuous hitting test; isokinetic testing.Data collection: the hitting strength, the number of strikes, the relative peaktorque, relative to the average power of flexor and extensor peak torque ratio, EMGrms, muscle contribution, muscle co-activator, operating time, the peak peak valueand time ratio of the joint line speed, the peak value and time ratio of joint angularvelocity, the minimum angle and time ratio of knee joint, the maximum angle and thetime ratio of knee angle, the contribution of joint rotational energy, support legstorque and time ratio. Research results:(1) The relative strikes strength of whipping-kick action about excellent group isrelatively bigger than normal group, and there are very significant differencesbetween the two groups. The right whipping-kick strength is bigger than left leg andthere exists significant differences between low whip legs. Sorted by strikes atdifferent height of whipping-kick movements: low whipping-kick leg> middlewhipping-kick leg> high whip leg, there are significant differences between left lowwhipping-kick leg and left high whipping-kick leg in excellent group, and right lowwhipping-kick leg and right high whipping-kick leg have extremely significantdifferences, left middle whipping-kick leg and left high whipping-kick leg havesignificant differences. The ordinary group has significant differences in the right lowwhipping-kick leg and right middle whipping-kick leg, right low whipping-kick legand right high whipping-kick leg have extremely significant differences.(2) For average relative strikes and numbers of30seconds continuous batter,excellent group is greater than normal group, there are significant differences in strikestrength. The average relative strikes strength and numbers of excellent group in first10seconds, middle10seconds, last10seconds is bigger than normal group, the last10seconds of strikes strength has significant differences. Ranked by the averagerelative strikes strength and numbers: first10seconds>middle10seconds>lastseconds. The strike frequency of excellent group in first10seconds and middle10seconds has significant difference significant difference, first10seconds and last10seconds have extremely significant difference. The strike frequency of ordinary groupin first10seconds and middle10seconds, first10seconds and last10seconds haveextremely significant differences.(3) Relative to peak torque decreases with the speed increases, and the relativeto the peak torque trunk flexors60°/s,120°/s,180°/s of ordinary group isgreater than excellent group, others are less than excellent group, left hip extensor60°/s, the left hip flexor180°/s, right hip flexor180°/s, the right knee flexors120°/s, the trunk extensor180°/s have significant differences, the left hip flexors120°/s and right hip extensor120°/s have extremely significant differences.(4) Relative to the average power trunk flexors60°/s,120°/s,180°/s, leftknee extensor60°/s of ordinary group is greater than the excellent group, others areless than excellent group, right hip extensor60°/s, right hip flexor120°/s, rightknee flexors180°/s have significant differences, right hip extensors1.2°/s andright knee flexors120°/s have very significant differences. (5) The trunk120°/s flexion and extension muscle peak torque ratio of normalgroup and excellent group have significant differences, the Torso of180°/s flexionand extension muscle peak torque ratio of the two groups have extremely significantdifferences, others have no significant differences.(6) The biggest activation extent and contribution of muscles duringwhipping-kick leg movement is left rectus femoris, right rectus femoris, left lateralhead of gastrocnemius and right gastrocnemius lateral head. The antagonistic musclesof both knee joint and ankle joint shows co-activator phenomenon. The support leg’sankle joint has bigger co-activator extent.(7) Excellent group has shorter time than normal group during whipping-kick legmovement, left middle whipping-kick leg, left high whipping-kick leg havesignificant difference, right middle whipping-kick leg have extremely significantdifferences.(8) Line speed peak value: ankle> knee> hip, the joint line peak velocity ofexcellent group is higher than normal group, there are extremely significantdifferences in left low, left middle whipping-kick leg’s hip, right low, right middle,right high whipping-kick leg’s knee, left low, left middle, left high whipping-kickleg’s ankle. The line speed peak value about hip and knee is probably shows around60%and80%of the total operating time, the elite group and normal group there is nosignificant differences.(9) The knee’s angular velocity peak value is bigger than hip, the angularvelocity peak value of the right middle whip leg’s knee for excellent group is smallerthan normal group, others are bigger than normal group, left low whip leg’s knee hasvery significant differences. The angular velocity peak value of hip appears earlierthan knee.(10) The minimum, maximum angle of against leg knee is respectively around70°and140°, minimum and maximum angle of against leg appears about70%andabout95%in total operating time.(11) The hip’s rotational energy contribution is less than knee, rotational energycontribution on whipping-kick leg’s hip of excellent group is bigger than normalgroup and it has significant differences, rotational energy contribution onwhipping-kick leg’s knee of excellent group is less than normal group, it hassignificant differences, others has no significant differences.(12) Supporting leg’s first torque peak value in excellent group is bigger thannormal group and there is no significant difference. Except right and left whipping-kick legs, the second torque peak value of excellent group is less thannormal group; others are bigger than normal group. The first and second torque peakvalue appears around20%and80%of total operating time.Conclusion:1. The whipping-kick leg strikes effectiveness of excellent Sanda athletes is betterthan ordinary athletes; the strike effectiveness of right whipping-kick leg is betterthan left; the sequence of whipping-kick leg strike effectiveness at different height islow whipping-kick leg> middle whipping-kick leg> high whipping-kick leg. Factorsaffecting combat effectiveness include movement speed, the link line speed, musclestrength, muscle coordination ability and so on.2. Excellent Sanda athletes’ power endurance and speed endurance are better thanordinary athletes; compared with normal athletes, elite athletes have better continuousstrike capability in whip movements.3. Except abdominal strength and abdominal work capacity of elite athletes areless than ordinary athletes, elite athletes’ other parts of the muscle strength andmuscle work capacity are better than ordinary athletes. The stability of Sanda athletes’left and right knees decreases with movement speed increases, thus we should paymore attention to train knees’ stability.4. The bigger activation and contribution of muscles on whipping-kick action isleft rectus femoris, right rectus femoris, left gastrocnemius and right gastrocnemius,so athletes should attach importance muscle training. Excellent athletes’ activationand contribution of muscles is relatively reasonable.5. Elite athletes’ movement speed is faster than normal athletes. The linearvelocity and angular velocity peak about excellent athletes’ whipping-kick leg jointsare bigger than normal athletes; the minimum knee angle of whipping-kick leg isabout70°, the maximum angle of whipping-kick leg is about140°.6. The knee rotational energy contribution during whipping-kick movements isgreater than the hip. The support legs in the whipping-kick action appears twice thepeak torque value, the first peak torque is greater than second. The positive reverse ofsupport during whipping-kick movements is helpful to increase whipping-kickeffectiveness and movement speed.7. Combat effectiveness, joint muscle strength, movement speed, part of thelinear velocity and angular velocity, the degree of muscle EMG activation and thecontribution of the supporting leg torque, combat leg knee angle can be used to evaluate the pros and cons of Sanda whipping-kick leg. Comprehensive evaluation ofelite athletes’ whipping-kick technology is better than ordinary athletes.