School of Human Sciences (Exercise and Sport Science), University of Western Australia, Crawley, WA, Australia.
ISSUL, Institute of Sports Sciences, University of Lausanne, Lausanne, Switzerland.
Int J Sports Physiol Perform. 2024 Jul 24;19(9):958-962. doi: 10.1123/ijspp.2024-0028. Print 2024 Sep 1.
We examined changes in stride temporal parameters and spring-mass model characteristics during repeated sprints following a 3-week period of "live high-train low and high" (LHTLH) altitude training in team-sport players.
While residing under normobaric hypoxia (≥14 h/d; inspired oxygen fraction [FiO2] 14.5%-14.2%) for 14 days, elite field hockey players performed, in addition to their regular field hockey practice in normoxia, 6 sessions (4 × 5 × 5-s maximal sprints; 25-s passive recovery; 5-min rest) under either normobaric hypoxia (LHTLH; FiO2 ∼14.5%, n = 11) or normoxia (live high-train low; FiO2 20.9%, n = 12). A control group (live low-train low; FiO2 ∼20.9%, n = 9) residing in normoxia without additional repeated-sprint training was included. Before (Pre) and a few days (Post-1) and 3 weeks (Post-2) after the intervention, stride mechanics were assessed during an overground repeated-sprint test (8 × 20 m, 20-s recovery). Two-way repeated-measures analysis of variance (time [Pre, Post-1, and Post-2] × condition [LHTLH, live high-train low, and live low-train low]) were conducted.
Peak sprinting speed increased in LHTLH from Pre to Post-1 (+2.2% [2.0%]; P = .002) and Post-2 (+2.0% [2.4%]; P = .025), with no significant changes in live high-train low and live low-train low. There was no main effect of time (all P ≥ .062), condition (all P ≥ .771), or a significant time × condition interaction (all P ≥ .230) for any stride temporal variable (contact time, flight time, stride frequency, and stride length) or spring-mass model characteristics (vertical and leg stiffness).
Peak sprinting speed improved in elite field hockey players following LHTLH altitude training, while stride mechanical adjustments to repeated overground sprints remained unchanged for at least 3 weeks postintervention.
我们研究了经过 3 周“高住低训”（LHTLH）海拔训练后，团队运动运动员在重复冲刺过程中步幅时间参数和弹簧质量模型特征的变化。
在 14 天内居住在常压缺氧环境中（≥14 小时/天；吸入氧分数[FiO2]为 14.5%-14.2%），除了在常氧下进行常规曲棍球训练外，11 名精英曲棍球运动员还进行了 6 次（4×5×5 秒最大冲刺；25 秒被动恢复；5 分钟休息）在常压缺氧（LHTLH；FiO2约 14.5%，n=11）或常氧（高住低训；FiO2 20.9%，n=12）下的训练。包括一个居住在常氧环境中且没有额外重复冲刺训练的对照组（低住低训；FiO2 约 20.9%，n=9）。干预前（Pre）和几天后（Post-1）以及 3 周后（Post-2），在地面重复冲刺测试（8×20m，20s 恢复）期间评估步幅力学。进行了双向重复测量方差分析（时间[Pre、Post-1 和 Post-2]×条件[LHTLH、高住低训和低住低训]）。
LHTLH 组从 Pre 到 Post-1（+2.2%[2.0%]；P=0.002）和 Post-2（+2.0%[2.4%]；P=0.025）的冲刺速度峰值均增加，而高住低训和低住低训组无显著变化。对于任何步幅时间变量（接触时间、腾空时间、步频和步长）或弹簧质量模型特征（垂直和腿部刚度），时间（所有 P≥0.062）、条件（所有 P≥0.771）或时间×条件交互作用（所有 P≥0.230）均无主要影响。
在 LHTLH 海拔训练后，精英曲棍球运动员的冲刺速度峰值提高，而至少在干预后 3 周内，重复地面冲刺的步幅力学调整保持不变。
