背景:跑步锻炼是增强心肺健康和身体成分的有效手段。除了这些健康益处,跑步也与肌肉骨骼损伤有关,这种损伤在体重过重的个体中更为普遍。关于跑步过程中超重和脚内旋对地面反作用力分布的具体影响知之甚少。因此,本研究旨在探讨超重/肥胖和足内旋对跑步动力学的影响。
方法:将84名年轻成年人分为四个实验组:非体重过重/非内旋脚;非体重过重/内旋脚;超重或肥胖/非内旋脚和超重或肥胖/内旋脚。生物力学测试包括参与者以〜3.2m/s的速度在18米长的人行道上奔跑,该人行道的中点装有嵌入式测力板。记录三维地面反作用力,并将其标准化为体重,以评估20次跑步试验的跑步动力学。运行速度数据的测试-重新测试可靠性表明,每组ICC>0.94。
结果:结果表明垂直冲击峰值力明显较低(p=0.001,效应大小=0.12),体重过重(超重或肥胖/非内旋脚组和超重或肥胖/内旋脚)的个体达到垂直冲击峰的时间更短(p=0.006,效应大小=0.08),垂直负荷率降低(p=0.0007,效应大小=0.13)。此外,体重过重组呈现较低的峰值制动(p=0.01,效应大小=0.06)和推进力(p=0.003,效应大小=0.09),较低的中侧向负荷率(p=0.0009,效应大小=0.12),与非超重组相比,自由力矩更大(p=0.01,效应大小=0.07)。此外,通过脚内旋相互作用发现了显着的体重,以达到峰值中外侧负荷率。非超重/内翻脚,与非超重/非内旋足相比,超重/非内旋足和超重/内旋组的中侧负荷率较低(p=0.0001,效应大小=0.13).
结论:我们的结果表明,体重过重对跑步过程中的地面反作用力有影响。我们特别注意到在站立阶段,中侧向力和扭转力的增加。体重过重的人似乎会调整自己的跑步方式,以减轻早期的垂直冲击负荷。
BACKGROUND: Running exercise is an effective means to enhance cardiorespiratory fitness and body composition. Besides these health benefits, running is also associated with musculoskeletal injuries that can be more prevalent in individuals with excessive body weight. Little is known regarding the specific effects of overweight and foot pronation on ground reaction force distribution during running. Therefore, this study aimed to investigate the effects of overweight/obesity and foot pronation on running kinetics.
METHODS: Eighty-four young adults were allocated to four experimental groups: non-excessive body weight/non-pronated feet; non-excessive body weight/pronated feet; overweight or obesity/ non-pronated feet and overweight or obesity/pronated feet. Biomechanical testing included participants to run at ~ 3.2 m/s over an 18-m walkway with an embedded force plate at its midpoint. Three-dimensional ground reaction forces were recorded and normalized to body mass to evaluate running kinetics from 20 running trials. Test-re-test reliability for running speed data demonstrated ICC > 0.94 for each group and in total.
RESULTS: The results indicated significantly lower vertical impact peak forces (p = 0.001, effect size = 0.12), shorter time to reach the vertical impact peak (p = 0.006, effect size = 0.08) and reduced vertical loading rate (p = 0.0007, effect size = 0.13) in individuals with excessive body weight (overweight or obesity/non-pronated feet group and overweight or obesity/pronated feet) compared with individuals non-excessive body weight (non-excessive body weight/non-pronated feet and non-excessive body weight/pronated feet). Moreover, the excessive body weight groups presented lower peak braking (p = 0.01, effect size = 0.06) and propulsion forces (p = 0.003, effect size = 0.09), lower medio-lateral loading rate (p = 0.0009, effect size = 0.12), and greater free moments (p = 0.01, effect size = 0.07) when compared to the non-overweight groups. Moreover, a significant body mass by foot pronation interaction was found for peak medio-lateral loading rate. Non-excessive body weight/pronated feet, excessive body weight/non-pronated feet and excessive body weight/pronation groups presented lower medio-lateral loading rates compared to non-excessive body weight/non-pronated feet (p = 0.0001, effect size = 0.13).
CONCLUSIONS: Our results suggest that excessive body weight has an impact on ground reaction forces during running. We particularly noted an increase in medio-lateral and torsional forces during the stance phase. Individuals with excessive body weight appear to adapt their running patterns in an effort to attenuate early vertical impact loading.