【作者】 袁艳；

【导师】 吴贻刚；

【作者基本信息】 上海体育学院 ， 体育教育训练学， 2013， 博士

【摘要】 研究目的：通过分析肌电图，探讨负重和振动刺激对大学生半蹲起下肢肌肉激活的影响；通过比较不同频率振动刺激对大学生半蹲起下肢肌肉激活的差异，找出引起最大肌肉激活的振动频率。制定具体振动训练方案，通过8周训练干预，观察其对大学生下肢肌肉最大力量、快速力量、H反射和T反射的影响并比较其差异，以此分析负重振动力量训练的神经肌肉适应特征并探讨其可能的机制。通过本研究丰富和完善负重振动训练的理论体系，并为普通人群和运动员振动力量训练方案的制定提供参考。研究方法：研究一：以10名男性大学生为研究对象。被试无负重在振动台上完成4组半蹲起，(1)不附加振动刺激；(2)附加频率为30Hz的振动刺激；(3)附加频率为40Hz的振动刺激；(4)附加频率为50Hz的振动刺激。然后以负重30%1RM负荷再完成4组相同控制条件的半蹲起。半蹲起过程中采用美国Noraxon公司的无线肌电遥测系统记录下肢8块肌肉肌电图。肌电的标准化采用肌电均方根值（EMGrms）除以肌肉最大等长收缩（MVC）时EMGrms再乘以100，表示为EMGrms(%MVC)。研究二：以16名男性田径专修大学生为研究对象，随机分为常规力量训练组（常规组）和振动力量训练组（振动组）。常规组完成30%1RM负重半蹲起训练，振动组采用台湾期美公司振动训练仪附加振幅为2mm、频率50Hz的振动刺激，完成相同负重半蹲起训练。8周训练前后，采用瑞士Kistler测力台测试半蹲跳和原地纵跳，记录生物力学数据。采用美国Alpin keypoint.net肌电/诱发电位仪和美国Noraxon公司的肌电遥测系统，测试H反射、T反射等神经适应指标。研究结果：在半蹲起运动中，振动刺激和负重对下肢肌群EMGrms(%MVC)影响结果，经双因素方差分析，振动刺激对所测肌肉EMGrms（%MVC）均有显著影响(p<0.05)；负重对股直肌、股外侧肌、股内侧肌、腓肠肌EMGrms（%MVC）有非常显著影响(p<0.05)，但对股二头肌、半腱肌、胫骨前肌无显著影响(p>0.05)；振动刺激和负重对所测肌肉肌电的交互作用均不显著(p>0.05)。在负重30%1RM条件下，随着振动频率的增加，所测肌群EMGrms（%MVC）均呈增加趋势，多重比较结果显示：在50Hz振动刺激中各块肌肉肌电均与相同负重不附加振动刺激时肌电有显著差异。8周力量训练前后，常规组和振动组组内半蹲跳蹬伸相对最大力量、相对快速力量指数、原地纵跳绝对腾空高度和弹性能利用率均提高，且实验前后存在显著性差异。两组间相对快速力量指数、原地纵跳绝对腾空高度和弹性能利用率增加值均有显著性差异。8周力量训练前后，振动力量训练组，组内H反射潜伏期、Hmax/Mmax和T反射潜伏期减小且差异具有显著性；H反射突触前抑制（PSI）和T反射振幅升高且具有显著性。组间H反射潜伏期、Hmax/Mmax、 PSI有显著性差异。研究结论与训练学意义：1.在半蹲起运动中，附加振动刺激可以显著提高下肢肌肉激活；负重30%最大力量可以显著提高半蹲起主动肌激活，不能提高对抗肌激活；负重和振动刺激对所测肌肉激活的交互作用均不显著。2.负重30%1RM半蹲起时，附加振幅为2mm、振动频率为50Hz的垂直振动刺激可以显著增加下肢主动肌和对抗肌激活。证明了在常规负重训练中附加振动刺激可以诱发激活更多的运动单位参与工作，并且有利于主动肌与对抗肌的协调发展，这为振动力量训练提供理论依据并为全身振动训练的频率选择提供参考。3.8周附加振动刺激的负重30%1RM力量训练对快速力量的提高优于相同负重的常规力量训练，训练方案适合田径跑跳等下肢弹性屈伸动作占主导的运动项目运动员。4.8周负重振动力量训练的神经肌肉适应表现为下肢快速力量的增加，同时伴随着α运动神经元和肌梭兴奋性的改变。负重振动力量训练的神经适应不仅出现在运动传导路上，而且也出现在相关的感受器上。更多还原

【Abstract】 Purpose:One purpose of this research was to examine if the addition ofwhole-body vibration and30%1RM external load would enhance increasesin muscle activity during dynamic squatting in8leg muscles and find thevibration frequency which activated maximal muscle activity. The otherpurpose was to study whether whole body vibration (WBV) combined withconventional resistance training (CRT) induce a higher increase inneuromuscular measures compared with CRT. The results enrich anddevelop the training’s theory system and provide reference for WBVtraining program.Methods:Ten healthy male performed a series of dynamic squats (unloaded withno WBV, unloaded with WBV, loaded with no WBV, and loaded withWBV). The load was set to30%of maximum force and WBV included30-,40-,50-Hz frequencies with2-mm amplitude. Muscle activity was recordedwith surface electromyography (EMG) on the rectus femoris (RF), vastusmedialis (VM), vastus lateralis (VL), biceps femoris (BF), tibialis anterior(TA), semitendinosus (SEM), and gastrocnemius (GC) and is reported asEMGrms (root mean square) normalized to%maximal voluntary contraction(MVC).Sixteen male college students who major in track and field wererandomized in two groups; squat only (S) and combination of WBV andsquat (S+V). They were participated in training programs three times aweek. S+V performed eight sets with ten repetitions with corresponding30%1RM loads on the vibrating platform (ZenPro TVR-5930, Taiwan,China), whereas S performed the same protocol without vibration. Thefrequency (50Hz) was chosen after the first studies. Squat jump (SJ),counter movement jump (CMJ), presynpatic inhibition (PSI), the T-reflexand H-reflex were measured before and after training. We analyzed thedifferences of neural adaptation and strength adaptation, applyingindependent-Samples t-test between groups and a paired t-test within eachgroup. Results:A two-factor ANOVA analysis of variance showed that vibrationstimulation had significant effect on EMGrms of all the muscles (P<0.05),and loads had significant effect on EMGrms of RF,VM,VL and GC (P<0.05).There was no significant interaction between vibration and load. Aftermultiple comparisons, it was found that exposure to WBV only50Hzsignificantly increased baseline muscle activity in all muscles.Applying t test within each group revealed that relative maximumstretch force of SJ, CMJ height, relative speed strength index, thecontribution of the stretch-shortening cycle (SSC) to jumpingperformance increased in WBV and CRT after training (P<0.05). H latency,Hmax/Mmax and T latency were significantly reduced, and PSI and Tamplitude were significantly increased only in S+V after training. T testshowed significant changes between groups after training in value-added ofCMJ height, relative speed strength index, the contribution of the SSC tojumping performance and H latency, Hmax/Mmax and PSI.Conclusions:It is suggested that WBV can increase the neuromuscular activity ofthe squat exercise in lower-extremity muscles. During dynamic squats,loads can increase the neuromuscular activity of agonistic muscle but cannot increase the neuromuscular activity of antagonist.During30%1RM loaded dynamic squats, exposure to WBV (50Hz,2mm) increased the neuromuscular activity of agonist and antagonist inlower limbs. The results demonstrate that the WBV can improve thesynchronization of motor unit and coordinating development betweenagonist and antagonist in the loaded condition.During30%1RM loaded dynamic squats, exposure to WBV is betterthan without WBV for increases in speed strength.Neuromuscular adaptation induced by weight whole-body vibrationtraining confirms the occurrence of changes in mechanical properties andthe excitability of the motoneurons and muscle spindle. This proposalwould indicate that neuromuscular adaptation is not only limited to themotor pathway to the muscle, but also concerns its sensory part.更多还原