体育课不同持续性运动时间和强度对初中生体成分的影响

探究体育课不同运动强度和持续性运动时间对初中生体成分的影响,为初中生体育课有效运动负荷的安排提供参考依据.方法 上海市某中学共6个班级226名学生参与实验干预.在3×40 min/周、共8周的体育课中,各班级分别嵌入15,10或5 min的大强度或中等强度持续性运动.结果 学生体质量指数(BMI)和腰臀比(WHR)呈现不同的变化幅度,前后测和班级间差异均无统计学意义.在体脂肪量(SFV)上,实验6班学生前后测差异有统计学意义(P=0.01);在去脂体重(FFM)上,实验2班、3班、4班、5班和6班学生前后测差异均有统计学意义;在体脂肪率(PBF)和去脂体重百分比(PFFM)上,各班级学生间差异无统计学意义,但呈现出不同的变化幅度;在肌肉量(LMM)上,实验2班、4班、5班和6班学生前后测差异均有统计学意义(P值均<0.05);在肌肉量百分比(PLMM)上,实验1班、4班和6班学生前后测差异均有统计学意义(P值均<0.05).结论 体育课10 min以上持续性大强度运动和15 min持续性中等强度运动可以提高学生PFFM,降低学生PBF;体育课5 min以上持续性大强度运动和15 min持续性中等强度运动可以提高学生PLMM.

Impact of exercise duration and intensity during physical education class on body composition among junior high school students

Objective To examine the effects of exercise duration and intensity on body composition among junior high school students,and to provide scientific basis for arranging the effective amount of exercise for junior high school students.Methois A total of 226 students from 6 classes participated this experimental trial.Different duration×intensity exercise elements were introduced into physical education class (40 min 3 times a week for 8 weeks),including 15,10 or 5 minutes vigorous and moderate exercise.Results The results showed no significant differences in the body mass index and waist-hip ratio pre-and post-experimental trial.Significant difference in somatic fat volume was only observed in group 6;for the fat free mass index,significant differences were found in group 2,group 3,group 4,group 5,group 6.The difference of PBF and PFFM was not statistically significant in each class students.For the lean muscle mass index,significant changes were observed in the experimental group 2,group 4,group 5 and group 6(P<0.05).There was significant differences in percentage of lean muscle mass index for experiment group 1,group 4,group 6(P<0.05).Conclusion Vigorous exercise for 10 min and moderate exercise for 15 min can increase percentage of fat free mass and decrease percentage of body fat.Vigorous exercise for 10 to 15 min and moderate exercise for 15 min during physical education class can help increase percentage of lean muscle mass.