Haugnes Pål, Kocbach Jan, Luchsinger Harri, Ettema Gertjan, Sandbakk Øyvind
Int J Sports Physiol Perform. 2019 Nov 1;14(10):1371-1377. doi: 10.1123/ijspp.2018-1007.
To investigate fluctuations in speed, work rate, and heart rate (HR) when cross-country ski skating across varying terrains at different endurance-training intensities.
Seven male junior Norwegian skiers performed maximal-speed (Vmax) tests in both flat and uphill terrains. Thereafter, 5-km sessions at low (LIT), moderate (MIT), and high intensity (HIT) were performed based on their own perception of intensity while monitored by a global navigation satellite system with integrated barometry and accompanying HR monitor.
Speed, HR, and rating of perceived exertion gradually increased from LIT to MIT and HIT, both for the total course and in flat and uphill terrains (all P < .05). Uphill work rates (214 [24] W, 298 [27] W, and 350 [54] W for LIT, MIT, and HIT, respectively) and the corresponding percentage of maximal HR (79.2% [6.1]%, 88.3% [2.4]%, and 91.0% [1.7]%) were higher than in flat terrain (159 [16] W, 206 [19] W, and 233 [72] W vs 72.3% [6.3]%, 83.2% [2.3]%, and 87.4% [2.0]% for LIT, MIT, and HIT, respectively) (all P < .01). In general, ∼13% point lower utilization of maximal work rate was reached in uphill than in flat terrain at all intensities (all P < .01).
Cross-country ski training across varying terrains is clearly interval based in terms of speed, external work rate, and metabolic intensity for all endurance-training intensities. Although work rate and HR were highest in uphill terrain at all intensities, the utilization of maximal work rate was higher in flat terrain. This demonstrates the large potential for generating external work rate when uphill skiing and the corresponding downregulation of effort due to the metabolic limitations.
研究在不同耐力训练强度下，越野滑雪在不同地形上滑行时速度、工作率和心率（HR）的波动情况。
7名挪威男性青少年滑雪运动员在平坦和上坡地形上进行了最大速度（Vmax）测试。此后，在全球导航卫星系统结合气压测量和配套心率监测仪的监测下，根据他们自己对强度的感知，分别进行了低强度（LIT）、中等强度（MIT）和高强度（HIT）的5公里训练。
无论是全程还是在平坦和上坡地形上，速度、心率和主观用力程度评分从低强度到中等强度再到高强度均逐渐增加（所有P < 0.05）。上坡工作率（低强度、中等强度和高强度分别为214 [24] W、298 [27] W和350 [54] W）以及相应的最大心率百分比（分别为79.2% [6.1]%、88.3% [2.4]%和91.0% [1.7]%）均高于平坦地形（低强度、中等强度和高强度分别为159 [16] W、206 [19] W和233 [72] W，以及72.3% [6.3]%、83.2% [2.3]%和87.4% [2.0]%）（所有P < 0.01）。总体而言，在所有强度下，上坡时最大工作率的利用率比平坦地形低约13个百分点（所有P < 0.01）。
对于所有耐力训练强度，越野滑雪在不同地形上的训练在速度、外部工作率和代谢强度方面明显基于间歇训练。尽管在所有强度下，上坡地形的工作率和心率最高，但平坦地形的最大工作率利用率更高。这表明上坡滑雪时产生外部工作率的潜力很大，以及由于代谢限制而相应地降低了用力程度。
