一种用于评估前进爬行游泳增加质量的新方法
Remi Carmigniani1, Vittorio Coloretti2, Thomas Brunel1
1LHSV, ENPC, Institut Polytechnique de Paris, EDF R&D, Chatou, France.
Journal of biomechanics
|June 17, 2025
概括
游泳者在起跑和转时体验增加的质量 (MA,a),影响加速. 一种新的站立启动测试方法量化了这一点,发现MA,a类似于被动条件,但具有更高的可变性.
科学领域:
- 运动科学 运动科学 运动科学
- 生物力学 生物力学
- 流体动力学 流体动力学
背景情况:
- 游泳者在起跑和转时面临非恒定速度,遇到超越阻力的惯性力.
- 增加的质量 (MA,a) 代表游泳者加速的水,在加速阶段增加阻力.
- 准确量化MA,a对于理解和改善游泳表现至关重要.
研究的目的:
- 引入和验证一种用于确定水面游泳中增加质量的新方法 (MA,a).
- 为了比较活动游泳期间的MA,a与被动增加的质量 (MA,p).
- 调查导致MA,a.的变化因素.
主要方法:
- 在16名男子游泳者身上进行了站立起跑最大测试.
- 瞬间速度是用一个IMU测量在圣骨上.
- MA,a是使用最大速度 (vmax),加速度时间 (τ),主动阻力系数 (ka) 和平均推进力 (FP) 来估计的.
主要成果:
- 这种新方法的平均值为:vmax = 1.73 m/s, τ = 1.14 s,FP = 146.8 N,ka = 47.9 kg/m.
- 平均MA,a是身体质量的28.7% (M0),相当于被动增加的质量 (MA,p=25%).
- 与MA,a相比,观察到MA,a的变异性显著更大,这与主动和被动阻力比率 (ka/kp) 无法解释.
结论:
- 站立起步最大测试提供了一种可靠的方法来量化游泳中增加的质量.
- 在水面游泳中增加的质量类似于被动条件,但表现出更大的个体间变化.
- 需要进一步的研究来确定活跃增加质量的变化来源.
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