Sports Majors Back Flexion Muscles Strength Characteristics

Objective: The muscle of trunk is very important.not only mainly constitues the part of body,but also sticks up for spinal column posture and stabilization.Many study have indicated that the stength of trunk Flexor-extensor is high related to low back pain. Tllis paper intends to do a research on healthy college students of physical education department of shandong normal university at different angular velocities,different range of motion and different specialty using CON-TREX TP500 trunk isokinetic testing system with isokinetic ballistic gravity correction mode. 20).These data of the healthy young collegiers could provide some knowledge of the characteristics of the trunk muscle and bebenefieal to the spots training,as well as the prevention of the low back pain and trunk muscle taining. method:All the ietms were tested using CON-TREX TP500 trunk isokinetic testing system with isokinetic ballistic gravity correction mode. (1)The indices of flexor-extensor strength during repeat(13 sets) trunk isokinetic concentric training at different angular velocities(45,90,135°/s) were measured and assessed respectively using CON-TREX TP500 trunk isokinetic testing system with isokinetic ballistic gravity correction mode in ten healthy male students from physical education department.(2) The indices of flexor-extensor strength of different range of motion(+15°—-20°,+15°—-55°,+15°—-90°,+15°—-90°,-20°—-90°,-55°—-90°)were measured and assessed respectively using CON-TREX TP500 trunk isokinetic testing system with isokinetic ballistic gravity correction mode in seventeen healthy male students from physical education department.(3)the study of different specialty(Physical Education,aerobic,ssocial sports,sports dance,ethnic traditional sports )were tested at angular velocities(45°/s).Results (1)①The peak torques of extensor and flexor increased early and than decreased at all three angular velocities as the repeat sets increased, while up to the 7th set (135°/s) the decrease became significantly (P<0.05).②The peak torques between the third and the fourth set of the first 6 sets at three angular velocities had very high correlation (pearson correlation more than 0.8).③A ccording to the data of the third and the fourth sets,the peak torque of extensor at 45°/s was significantly lower than that at 90°/s and at 135°/s(P<0.01);the flexor/extensor of peak torque was on the contrary.The differences of positions average at peak torque between flexor and extensor were very significantly (P<0.01) at 45°/s and 90°/s,but at 135°/s (P>0.05).(2)The data between different range of motion have significant difference.(3)The peak torque,power average and total work values of male extensor,male flexors Was higher than the females.Conclusion (1) The isokinetic concentric strength training of trunk flexors and extensors should chose 3-6 sets and at slow or medium speed.(2) The data between different range of motion have significant difference.The datas 0f the third and the forth sets during the repeated measures are more steable than the datas of other sets.(3) The peak torque,power average and total work values of male extensor,male flexors Was higher than the females.The trunk steability of the aerobic(male female)and the Physical Education(female),sports dance(female) are higher than the runk steability of others at angular velocities(45°/s).