Macdermid Paul W, Osborne Aaron, Stannard Stephen R
School of Sport and Exercise, College of Health, Massey University, Palmerston North, New Zealand.
Canoe Slalom New Zealand, Auckland, New Zealand.
Front Physiol. 2019 Mar 20;10:260. doi: 10.3389/fphys.2019.00260. eCollection 2019.
The purpose of this study was to assess the physical work demand in relation to metrics of force and subsequent physiological response to a simulated flatwater slalom competition. Eight New Zealand team members completed a standard incremental step-test to ascertain power:oxygen consumption relationship. This was followed by a simulated race run where breath-by-breath analysis along with force and power data logged at 50 Hz to determine stroke length, impulse, peak force, time to peak force, and rate of peak force per stroke. Physiological response to negotiating a flatwater slalom course was greater than straight-line paddling (36.89 ± 2.01 vs. 32.17 ± 1.97 ml⋅kg⋅min, = 0.0065) at the same power output. Mean power output for the duration of the simulated race (91.63 ± 7.19 s) was 203.8 ± 45.0 W, incurring an oxygen deficit of 1.386 ± 0.541 L⋅min translating to an overall anaerobic contribution of 32 ± 18% and aerobic contribution of 68 ± 18%. Moderate to strong relationships between time duration and stroke peak force ( = 0.354, = 0.485) and rate of peak force development ( = 0.345, = 0.426) but not for stroke length ( = 0.022, = 0.012), impulse ( = 0.088, = 0.097) or time to peak force ( = 0.001, = 0.0001) for left and right strokes, respectively. The number of propulsive (<0.6 s) strokes outweighed turning/driving (>0.6 s) strokes with a ratio of 94:6%. Longer stroke duration was significantly correlated to greater impulse ( = 0.507, < 0.0001) and time to peak force ( = 0.851, < 0.0001), but a lower rate of force development ( = 0.107, < 0.0001). The results show that a flatwater slalom under simulated race conditions entails initial supra-maximal (anaerobic) work rate with a subsequent transition to one associated with maximal aerobic capacity. Inability to sustain work done and the subsequent decline in peak force and force profile per stroke requires further research regarding strategies to enhance performance.
本研究的目的是评估与力量指标相关的体力工作需求，以及模拟静水回旋赛中随后的生理反应。八名新西兰队队员完成了一项标准的递增台阶测试，以确定功率与耗氧量的关系。随后进行了一次模拟比赛，在此过程中进行逐次呼吸分析，并以50赫兹记录力量和功率数据，以确定划桨长度、冲量、峰值力量、达到峰值力量的时间以及每划桨的峰值力量变化率。在相同功率输出下，通过静水回旋赛道时的生理反应大于直线划桨（36.89±2.01对32.17±1.97毫升·千克·分钟，P = 0.0065）。模拟比赛持续时间（91.63±7.19秒）内的平均功率输出为203.8±45.0瓦，产生的氧亏为1.386±0.541升·分钟，总体无氧贡献率为32±18%，有氧贡献率为68±18%。持续时间与划桨峰值力量（r = 0.354，P = 0.485）以及峰值力量发展变化率（r = 0.345，P = 0.426）之间存在中度至强相关性，但划桨长度（r = 0.022，P = 0.01）、冲量（r = 0.088，P = 0.097）或左右划桨达到峰值力量的时间（r = 0.001，P = 0.0001）之间不存在相关性。推进性划桨（<0.6秒）的次数超过转向/驱动性划桨（>0.6秒），比例为94:6%。较长的划桨持续时间与更大的冲量（r = 0.507，P < 0.0001）和达到峰值力量的时间（r = 0.851，P < 0.0001）显著相关，但力量发展变化率较低（r = 0.107，P < 0.0001）。结果表明，模拟比赛条件下的静水回旋需要初始超最大（无氧）工作率，随后过渡到与最大有氧能力相关的工作率。无法维持所做的工作以及随后每划桨峰值力量和力量变化曲线的下降，需要进一步研究提高表现的策略。
