稳定状态循环期间的电力生产策略是依赖节奏的节奏
Yuta Yamaguchi1, Mitsuo Otsuka1, Naoki Wada1
1Faculty of Sport Science, Nippon Sport Science University, Setagaya, Japan.
Journal of biomechanics
|August 29, 2023
概括
赛道骑自行车的人随着踩踏节奏的增加,将动力生产从部延伸到膝盖延伸. 在每分钟180转时,部延伸变得负,需要特殊训练才能达到最佳性能.
科学领域:
- 运动科学 运动科学 运动科学
- 生物力学 生物力学
- 运动生理学 运动生理学
背景情况:
- 在骑自行车时,杆发电通常涉及部和膝关节的延伸/屈曲,低于每分钟120转 (rpm).
- 在赛道自行车运动中常见的120rpm以上的动力生产下肢协调策略在很大程度上仍然没有特征.
研究的目的:
- 为了研究不同踏板节奏 (90,120,150和180rpm) 在平稳状态骑行期间对下肢协调和动力生产策略的影响.
主要方法:
- 20名训练有素的大学生骑自行车者完成了30秒的稳定状态骑自行车比赛,他们在四个不同的节奏中以50%的最大无氧功率完成了比赛.
- 踏板力和四肢动力学分别使用踏板力测量系统和运动捕捉系统来捕获.
主要成果:
- 来自部延伸的积极机械工作随着踩踏节奏的增加而显著下降 (P < 0.05).
- 膝关节曲带来的正机械劳动在较高的节奏时显著增加 (P < 0.05).
- 在每分钟150转以上的节奏下,膝关节对机械工作总量贡献超过70%,而关节的贡献不到40%.
- 在每分钟180转时,部延伸工作从正向负的机械工作转移.
结论:
- 在稳定状态循环时,动力生产策略在180rpm时从根本上发生变化,与典型的踏板节奏有很大不同.
- 为了优化赛道自行车的表现,需要专注于过高的节奏 (例如,每分钟180转) 的特定训练方案.
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