等张训练对不良姿态大学生体型及颈肩部活动的改善效果

Effects of isotonic muscle exercise on body shape and neck-shoulder muscle activity of college students

目的分析2种训练方法对低体力活动伴不良身体姿态大学生的健康促进效果,为不良姿态大学生选择适宜的体育锻炼方式提供参考。方法经评估后将秦皇岛市某高校30名久坐伴有典型上交叉综合征特征者随机分成无负荷等张训练组(IT)、等张阻力训练组(RIT)、健康教育对照组(C),对实验组实施12周的等张训练。于训练前、后测试两组受试者的Heath-Carter体型、颈椎夹角、颈椎伸展、肩胛骨内收幅度、颈肩肌表面肌电信号数据。结果训练后IT、RIT、C组Heath-Carter的体型内、中、外3因子分别为[(3.68±1.01)(5.68±1.05)(3.17±0.54),(2.84±0.84)(5.87±1.45)(1.34±0.10),(3.82±0.18)(4.83±1.03)(3.30±0.22)],两实验组的中胚层增加,内、外胚层减小。训练后IT、RIT、C组的颈椎夹角分别为(32.70±9.20)(20.78±2.24)(11.24±3.21)°,颈椎伸展角度分别为(3.21±1.82)(2.24±0.60)(1.24±0.01)°,肩胛骨内收幅度分别为(3.44±1.28)(3.08±1.35)(6.08±1.57)cm,两实验组的3个指标均明显提高(F值分别为8.43,7.29,8.04,P值均<0.05)。训练后IT、RIT、C组的颈、肩部拮抗肌共激活比值分别为(0.11±0.01)和(0.34±0.02)(0.31±0.01)和(0.56±0.03)(0.36±0.11)和(0.69±0.04),两实验组的共激活比值均降低(F值分别为27.39,5.85,P值均<0.05)。颈肩部肌-骨系统活动特征以IT组的变化更为显著(P<0.05)。结论等张阻力训练增加肌-骨系统体积和减脂的效果更明显,无负荷等张训练对改善和纠正上交叉综合征姿势效果要优于等张阻力训练。久坐伴有不良姿态的大学生可优先选择无负荷等张训练,提高肌肉力量及协调性后再增加训练负荷。

Objective The purpose of this study was to investigate effects two kinds of isotonic muscle contraction training on muscle body shape and neck-shoulder muscle activity among college students with physical inactivity and poor body posture, to provide appropriate exercise options for these college students. Method Thirty subjects with typical sedentary behavior and upper-cross syndrome were randomly divided into no load isotonic training(IT),resistance isotonic training(RIT) and health education control(C) groups. Two training groups were trained for 12 weeks. All subjects were tested their heath-carter anthropometric somatotype,cervical spine angle,range of cervical spine extending and scapula adduction,surface electromyography data of neck and shoulder musle activity were measured before/after training. Results After training,three factors value in IT, RIT, C groups were[(3.68±1.01)(5.68±1.05)(3.17±0.54),(2.84±0.84)(5.87±1.45)(1.34±0.10),(3.82±0.18)(4.83±1.03)(3.30±0.22)] respectively. After training,cervical spine angles were(32.70±9.20)(20.78±2.24)(11.24±3.21)°;extending angles of cervical spine were(3.21±1.82)(2.24±0.60)(1.24±0.01)°;ranges of scapula adduction were(3.44±1.28)(3.08±1.35)(6.08±1.57)cm in IT, RIT, C groups respectively. Three parameters in two training groups significantly increased(F=8.43, 7.29, 8.04, P<0.05). Antagonistic muscle co-activation in neck and shoulder in three groups were(0.11±0.01) and(0.34±0.02)(0.31±0.01) and(0.56±0.03)(0.36±0.11) and(0.69±0.04) respectively,which significantly decreased in two training groups(F=27.39,5.45,P<0.05). There were more obviously changes of neck and shoulder muscle-bone system in IT group(P<0.05). Conclusion Musculoskeletal system improved while body fat reduced after resistance isotonic training. No load isotonic training was more superior in adjusting and correctingg upper-crossed syndrome posture than resistance isotonic training. College students with sedentary behavior and upper-cross syndrome can choose no load isotonic training preliminarily for muscle strength and concordance increasing before adding load.