Biology Center, China Institute of Sport Science, Beijing, China.
J Strength Cond Res. 2013 Jun;27(6):1511-9. doi: 10.1519/JSC.0b013e31826caef8.
Functional overreaching (FOR) represents intense training followed by a brief reduction in performance and then a rapid recovery (<2 weeks) and performance supercompensation. Nonfunctional overreaching (NFOR) occurs when the reduced performance continues ≥3 weeks. Heart rate variability (HRV) is a promising tool for detecting NFOR. In this study, the authors examined HRV thresholds in 34 elite female wrestlers (mean ± SD: age 23 ± 3 years; height 165.6 ± 6 cm, weight 63 ± 8 kg) for FOR/NFOR during training before 11 major competitions. Supine HRV was analyzed weekly at the same time of day using time and frequency domain methods. The authors observed that the time domain index, square root of the mean of the sum of the squares of differences between adjacent R-to-R intervals (rMSSD, milliseconds), denoting parasympathetic tone, showed those responding normally to training (82.76 ms, 95% confidence interval 77.75-87.78) to be significantly different to those showing a decrease (45.97 ms, 95% confidence interval, 30.79-61.14) or hyper-responsiveness (160.44 ms, 95% confidence interval, 142.02-178.85; all, p < 0.001). Similar results were observed for mixed sympathetic and parasympathetic signal standard deviation of the NN intervals (ms): normal (65.39; 95% confidence interval, 62.49-68.29), decrease (40.07; 95% confidence interval, 29-51.14), and hyperresponse (115.00; 95% confidence interval, 105.46-124.54; all, p < 0.001) and synonymous frequency domain components. An examination of the 95% confidence interval shows a narrow band surrounding a normal response compared with broader bands accompanying adverse responses. Thus, severe perturbations both above and below normal responses lasting >2 weeks indicated an athlete's transition to NFOR and, hence, are useful for assessing possible overreaching/training.
功能超越（FOR）代表在短暂的表现下降后进行高强度训练，然后快速恢复（<2 周）和表现超补偿。非功能超越（NFOR）发生在表现持续下降≥3 周时。心率变异性（HRV）是检测 NFOR 的一种有前途的工具。在这项研究中，作者检查了 34 名精英女摔跤手（平均±SD：年龄 23±3 岁；身高 165.6±6 厘米，体重 63±8 公斤）在 11 次重大比赛前的训练中 FOR/NFOR 期间的 HRV 阈值。使用时域和频域方法，每周在同一时间仰卧分析 HRV。作者观察到，时域指数，即相邻 R-R 间期均方根的平均值（rMSSD，毫秒），表示副交感神经活动，表现出正常训练反应（82.76 毫秒，95%置信区间 77.75-87.78）与表现出下降（45.97 毫秒，95%置信区间，30.79-61.14）或超反应（160.44 毫秒，95%置信区间，142.02-178.85；全部，p<0.001）的运动员有显著差异。对于混合交感和副交感神经信号的 NN 间期标准差（ms），也观察到类似的结果：正常（65.39；95%置信区间，62.49-68.29）、下降（40.07；95%置信区间，29-51.14）和超反应（115.00；95%置信区间，105.46-124.54；全部，p<0.001）和同义频域成分。对 95%置信区间的检查表明，与伴随不良反应的较宽频带相比，正常反应周围有一个狭窄的频带。因此，持续时间超过 2 周的严重上下超越正常反应表明运动员过渡到 NFOR，因此对于评估可能的过度训练/训练很有用。
