PDF(Pubmed)
Abstract：
Sport coaches increasingly rely on external load metrics for designing effective training programs. However, their accuracy in estimating internal load is inconsistent, and their ability to predict autonomic nervous system (ANS) deterioration is unknown. This study aimed to evaluate the relationships between internal and external training load metrics and ANS recovery and function in college football players. Football athletes were recruited from a D1 college in the southeastern US and prospectively followed for 27 weeks. Internal load was estimated via exercise cardiac load (ECL; average training heartrate (HR) × session duration) and measured with an armband monitor equipped with electrocardiographic capabilities (Warfighter MonitorTM (WFM), Tiger Tech Solutions, Miami, FL, USA). External load was estimated via the summation and rate of acceleration and decelerations as measured by a triaxial accelerometer using the WFM and an accelerometer-based (ACCEL) device (Catapult Player Load, Catapult Sports, Melbourne, Australia) worn on the mid-upper back. Baseline HR, HR variability (HRV) and HR recovery served as the indicators for ANS recovery and function, respectively. For HRV, two, time-domain metrics were measured: the standard deviation of the NN interval (SDNN) and root mean square of the standard deviation of the NN interval (rMSSD). Linear regression models evaluated the associations between ECL, ACCEL, and the indicators of ANS recovery and function acutely (24 h) and cumulatively (one- and two-week). Athletes (n = 71) were male and, on average, 21.3 ± 1.4 years of age. Acute ECL elicited stronger associations for 24 h baseline HR (R2 0.19 vs. 0.03), HR recovery (R2 0.38 vs. 0.07), SDNN (R2 0.19 vs. 0.02) and rMSSD (R2 0.19 vs. 0.02) compared to ACCEL. Similar results were found for one-week: 24 h baseline HR (R2 0.48 vs. 0.05), HR recovery (R2 0.55 vs. 0.05), SDNN (R2 0.47 vs. 0.05) and rMSSD (R2 0.47 vs. 0.05) and two-week cumulative exposures: 24 h baseline HR (R2 0.52 vs. 0.003), HR recovery (R2 0.57 vs. 0.05), SDNN (R2 0.52 vs. 0.003) and rMSSD (R2 0.52 vs. 0.002). Lastly, the ACCEL devices weakly correlated with ECL (rho = 0.47 and 0.43, p < 0.005). Our findings demonstrate that ACCEL poorly predicted ANS deterioration and underestimated internal training load. ACCEL devices may \"miss\" the finite window for preventing ANS deterioration by potentially misestimating training loads acutely and cumulatively.
摘要：
体育教练越来越依赖外部负荷指标来设计有效的训练计划。然而,它们估计内部负荷的准确性不一致，他们预测自主神经系统（ANS）恶化的能力是未知的。本研究旨在评估大学橄榄球运动员内部和外部训练负荷指标与ANS恢复和功能之间的关系。足球运动员是从美国东南部的D1大学招募的，并前瞻性地随访了27周。通过运动心脏负荷（ECL；平均训练心率（HR）×会话持续时间）估算内部负荷，并使用配备有心电图功能的臂章监测器（WarfighterMonitorTM（WFM），Tiger技术解决方案,迈阿密,FL,美国）。通过使用WFM和基于加速度计的（ACCEL）设备（弹射器播放器负载，弹射器运动，墨尔本,澳大利亚）穿着在中上背部。基线HR,HR变异性（HRV）和HR恢复作为ANS恢复和功能的指标，分别。对于HRV，两个,测量了时域指标：NN间隔的标准偏差（SDNN）和NN间隔的标准偏差的均方根（rMSSD）。线性回归模型评估了ECL，ACCEL,以及急性（24小时）和累积（一周和两周）的ANS恢复和功能指标。运动员（n=71）是男性，平均而言,21.3±1.4岁。急性ECL引起24h基线HR更强的关联（R20.19vs.0.03),HR恢复（R20.38vs.0.07),SDNN（R20.19vs.0.02）和rMSSD（R20.19vs.0.02）与ACCEL相比。一周后发现了类似的结果：24小时基线HR（R20.48vs.0.05),HR恢复（R20.55vs.0.05),SDNN（R20.47vs.0.05）和rMSSD（R20.47vs.0.05）和两周累积暴露：24小时基线HR（R20.52vs.0.003),HR恢复（R20.57vs.0.05),SDNN（R20.52vs.0.003）和rMSSD（R20.52vs.0.002).最后,ACCEL装置与ECL弱相关(rho=0.47和0.43,p<0.005)。我们的发现表明，ACCEL对ANS恶化的预测不佳，内部训练负荷被低估。ACCEL设备可能会“错过”用于防止ANS恶化的有限窗口，因为可能会急剧和累积地错误估计训练负荷。
