不同时长锻炼对膝关节等速肌力的影响

Effects of different duration of exercise on isokinetic muscle strength around knee

[目的]观察不同时长锻炼对膝关节屈伸肌群等速肌力的影响。[方法]选取在校大学生54人纳入本研究,采用随机数字法,将研究对象分为,10 s组11人、15 s组11人、20 s组11人、25 s组10人、30 s组11人。分别给予相应时长的膝关节功法锻炼,持续12周。采用Biodex S4等速测试系统,测试锻炼前与锻炼12周后,在角速度60°/s和180°/s的峰值力矩(peak torque,PT)、相对峰值力矩(peak torque/body weight,PT/BW)、平均功率(average power,AP)及屈伸肌比值(hamstring/quadriceps,H/Q)。[结果]与锻炼前相比,锻炼12周后在60°/s角速度下伸肌群测试,五组的PT、PT/BW均显著提高(P<0.05),10 s组、15 s组、20 s组和30 s组的AP显著提高(P<0.05);在180°/s角速度下,10 s、20 s、30 s组的PT、PT/BW和AP显著提高(P<0.05);其中20 s组和30 s组的变化最为显著。组间比较,相应时间点五组间上述指标的差异均无统计学意义(P>0.05)。在60°/s角速度下,10 s组、15 s组、20 s组、30 s组屈肌测试PT、PT/BW均显著提高(P<0.05),15 s组、20 s组、30 s组AP显著提高(P<0.05);在180°/s角速度下,10 s组、20 s组、30 s组PT、PT/BW、AP显著提高(P<0.05)。各组锻炼前后H/Q无显著变化(P>0.05),相应时间点,五组间H/Q的差异均无统计学意义(P>0.05)。[结论]传统功法锻炼有助于改善膝关节屈伸肌群最大肌力、爆发力及肌耐力。其中,时长为20 s及30 s的锻炼,对于膝关节屈伸肌力改善效果最显著。

[Objective]To observe the effects of different duration of exercise on the isokinetic strength of knee extensor and flexor.[Methods]A total of 54 college students were included into this study and divided into 5 groups by random number method.Of them,11 persons were in the 10-second group,11 in the 15-second group,11 in the 20-second group,10 in the 25-second group and 11 in the 30-second group,and corresponding duration of knee exercises conducted for 12 weeks.The Biodex S4 isokinetic test system was used to measure peak torque(PT),relative peak torque(peak torque/body weight,PT/BW),average power(AP)and hamstring/quadriceps(H/Q)at angular speeds of 60°/s and 180°/s before and 12 weeks after exercise.[Results]In term of extensor,the PT and PT/BW were significantly increased in all the 5 groups(P<0.05),and AP were significantly increased in the 10-second group,15-second group,20-second group and 30 second group at 60°/s angular velocity 12 weeks after exercise compared with those before exercise(P<0.05).Furthermore,the PT,PT/BW and AP were significantly increased in the 10-second group,20-second group and 30-second group at 180°/s angular velocity(P<0.05),with the most significant changes in the 20-second group and 30-second groups.There was no significant difference in the above indexes among the5 groups at any corresponding time point(P>0.05).In term of flexor,the PT and PT/BW were significantly increased in the 10-second group,15-scond group,20-second group and 30 second groups(P<0.05),and AP was significantly increased in the 15-second group,20-second group and 30-scond groups at 60°/s angular velocity(P<0.05),while the PT,PT/BW and AP in 10-second,20 second and 30-second groups were significantly increased at 180°/s angular velocity(P<0.05).However,there were no significant changes in H/Q before and after exercise in all the 5 groups(P>0.05),and there were no significant differences in H/Q among the five groups at any corresponding time points(P>0.05).[Conclusion]Traditional exercises does improve the maximum muscle strength,explosive power and muscle endurance of knee extensor and flexor.Among them,exercises lasting 20 seconds and 30 seconds have the most significant improvement in knee extensor and flexor strength.