Movement Sciences, Australian Institute of Sport, Bruce, ACT, Australia.
Int J Sports Physiol Perform. 2013 Mar;8(2):165-72. doi: 10.1123/ijspp.8.2.165.
The purpose of this study was to determine if Yo-Yo Intermittent Recovery level 2 (Yo-Yo IR2) and the number of interchange rotations affected the match activity profile of elite Australian footballers.
Fifteen elite Australian footballers completed the Yo-Yo IR2 before the beginning of the season and played across 22 matches in which match activity profiles were measured via microtechnology devices containing a global positioning system (GPS) and accelerometer. An interchange rotation was counted when a player left the field and was replaced with another player. Yo-Yo IR2 results were further split into high and low groups.
Players match speed decreased from 1st to 4th quarter, while average-speed (m/min: P = .05) and low-speed activity (LSA, <15 km/h) per minute (LSA m/min; P = .06) significantly decreased in the 2nd half. Yo-Yo IR2 influenced the amount of m/min, high-speed running (HSR, >15 km/h) per minute (HSR m/min) and accelerometer load/min throughout the entire match. The number of interchanges significantly influenced the HSR m/min and m/min throughout the match except in the 2nd quarter. Furthermore, the low Yo-Yo IR2 group had significantly less LSA m/min in the 4th quarter than the high Yo-Yo IR2 group (92.2 vs 96.7 m/min, P = .06).
Both the Yo-Yo IR2 and number of interchanges contribute to m/min and HSR m/min produced by elite Australian footballers, affecting their match activity. However, while it appears that improved Yo-Yo IR2 performance prevents reductions in LSA m/min during a match, higher-speed activities (HSR m/min) and overall physical activity (m/min and load/min) are still reduced in the 4th quarter compared with the 1st quarter.
本研究旨在确定 Yo-Yo 间歇性恢复水平 2（Yo-Yo IR2）和交替次数是否会影响精英澳式足球运动员的比赛活动模式。
15 名精英澳式足球运动员在赛季开始前完成 Yo-Yo IR2 测试，并参加了 22 场比赛，比赛活动模式通过包含全球定位系统（GPS）和加速度计的微技术设备进行测量。当一名球员下场并被另一名球员替换时，算作一次交替。Yo-Yo IR2 结果进一步分为高分组和低分组。
球员的比赛速度从第 1 节下降到第 4 节，而平均速度（m/min：P =.05）和每分钟低强度活动（LSA，<15km/h）（LSA m/min；P =.06）在下半场显著下降。Yo-Yo IR2 影响了整个比赛中每分钟的 m/min、高速跑（HSR，>15km/h）（HSR m/min）和加速度计负荷/min。交替次数显著影响了整个比赛中 HSR m/min 和 m/min，除了第 2 节。此外，低 Yo-Yo IR2 组在第 4 节的 LSA m/min 明显低于高 Yo-Yo IR2 组（92.2 比 96.7 m/min，P =.06）。
Yo-Yo IR2 和交替次数都对精英澳式足球运动员产生的 m/min 和 HSR m/min 有贡献，影响他们的比赛活动。然而，虽然似乎 Yo-Yo IR2 表现的提高可以防止比赛中 LSA m/min 的减少，但与第 1 节相比，第 4 节的高速活动（HSR m/min）和整体体力活动（m/min 和负荷/min）仍然减少。
