论文部分内容阅读
背景:研究显示,与脚后跟着地跑步模式相比,前脚掌着地跑步模式可通过降低冲击相关参数来降低引发跑步相关的过劳性损伤的风险。但现有研究仅比较了不同着地模式冲击参数的时域部分。由于冲击震动的频率成分和衰减度可能对损伤风险及预防非常重要,因此本研究旨在探究后脚跟着地和前脚掌着地跑步者的头部和胫骨加速信号功率以及冲击衰减方面的差别。方法:选取惯用后脚跟和前脚掌着地的跑步者各19名,让其按照各自习惯使用的着地模式,以3.5m/s的速度在跑步机上跑步,收集其胫骨和头部加速数据,计算第1和第2个头部加速峰值的量级和胫骨正向加速度峰值。计算各个信号的功率谱密度来转换头部加速度的频域部分,用相当于胫骨的头部信号的转换函数计算冲击衰减。结果:后脚跟着地时胫骨的正向加速度峰值和信号功率在较低和较高的范围内明显大于前脚掌着地(p<0.05)。第1和第2个头部加速度峰值和头部信号功率在两种跑步模式下均无明显差异(p>0.05)。后脚跟着地跑步模式下,由于胫骨加速度增大,冲击衰减度在较低和较高的范围内均会增大(p<0.05)。结论:不同跑步模式冲击震动频率成分不同,说明衰减的主要机制有差异。虽然冲击衰减机制和运动损伤间的关系尚不清晰,但因冲击成分不同,也许两种跑步模式都无法有效避免损伤,不同模式中的持续损伤类型各不相同。
Background: Studies have shown that, compared with heel-in-ground running mode, forefoot ground running mode reduces the risk of running-related overwork injuries by reducing impact-related parameters. However, the existing research only compares the time-domain part of impact parameters of different ground modes. Since the frequency components and attenuation of shock and vibration may be important for the risk of injury and prevention, the present study aimed to investigate the difference in head and shin speed signal power and impact attenuation between the heel and forefoot runners. Methods: Nineteen runners who used to base their heel and forefoot were selected to run on the treadmill at a speed of 3.5m / s according to the habitual land pattern they used. The tibia and head acceleration data were collected, 1 and the second head acceleration peak magnitude and tibial forward acceleration peak. The power spectral density of each signal is calculated to convert the frequency domain portion of the head acceleration, and the impact attenuation is calculated using the transfer function corresponding to the head signal of the tibia. Results: The tibial forward acceleration peak and signal power were significantly greater in the lower and higher regions than in the forefoot when heel-heeled (p <0.05). The first and second head acceleration peaks and head signal power were not significantly different between the two running modes (p> 0.05). In heel-to-ground running mode, the impact attenuation increased at lower and higher ranges due to increased tibial acceleration (p <0.05). Conclusion: The impact vibration frequency components of different running modes are different, indicating that there are differences in the main mechanisms of attenuation. Although the relationship between impact-attenuating mechanism and sports injuries is not clear, it may not be possible to avoid injury both running modes due to different impact components. The types of sustained injuries vary from model to model.