Staiano Walter, Bonet Lluis Raimon Salazar, Romagnoli Marco, Ring Christopher
Department of Physical Education and Sport, University of Valencia, Valencia,Spain.
Department of Psychology, Biological and Cognitive Psychology, University of Southern Denmark, Odense,Denmark.
Int J Sports Physiol Perform. 2023 Mar 9;18(5):465-473. doi: 10.1123/ijspp.2022-0356. Print 2023 May 1.
Mental fatigue (MF) can impair physical performance in sport. We tested the hypothesis that cognitive load alone, and intermixed with standard resistance training, would induce MF, increase rating of perceived exertion (RPE), alter perception of weight lifting and training, and impair cycling time-trial performance.
This 2-part study employed a within-participant design. In part 1, after establishing leg-extension 1-repetition maximum (1RM), 16 participants lifted and briefly held weights at 20%, 40%, 60%, and 80% of 1RM. RPE and electromyography (EMG) were measured for each lift. During the testing sessions, participants completed cognitive tasks (MF condition) or watched neutral videos (control condition) for 90 minutes before lifting the weights. In part 2, they completed submaximal resistance training comprising 6 weight training exercises followed by a 20-minute cycling time trial. In the MF condition, they completed cognitive tasks before and between weight training exercises. In the control condition, they watched neutral videos. Mood (Brunel Mood Scale), workload (National Aeronautics and Space Administration Task Load Index), MF-visual analogue scale (MF-VAS), RPE, psychomotor vigilance, distance cycled, power output, heart rate, and blood lactate were measured.
In part 1, the cognitive task increased lift-induced RPE (P = .011), increased MF-VAS (P = .002), and altered mood (P < .001) compared with control. EMG did not differ between conditions. In part 2, the cognitive tasks increased RPE (P < .001), MF-VAS (P < .001), and mental workload (P < .001), but reduced cycling time-trial power (P = .032) and distance (P = .023) compared with control. Heart rate and blood lactate did not differ between conditions.
A state of MF induced by cognitive load, alone or intermixed with physical load, increased RPE during weight lifting and training and impaired subsequent cycling performance.
精神疲劳（MF）会损害运动中的身体表现。我们检验了以下假设：单独的认知负荷以及与标准阻力训练混合时，会诱发MF，增加自觉用力程度（RPE）评分，改变对举重和训练的感知，并损害自行车计时赛成绩。
这项两部分的研究采用了参与者内设计。在第1部分中，在确定腿部伸展1次重复最大值（1RM）后，16名参与者以1RM的20%、40%、60%和80%举起并短暂保持重量。每次举重时测量RPE和肌电图（EMG）。在测试期间，参与者在举重前完成认知任务（MF条件）或观看中性视频（对照条件）90分钟。在第2部分中，他们完成了次最大阻力训练，包括6次重量训练练习，随后进行20分钟的自行车计时赛。在MF条件下，他们在重量训练练习之前和之间完成认知任务。在对照条件下，他们观看中性视频。测量了情绪（布鲁内尔情绪量表）、工作量（美国国家航空航天局任务负荷指数）、MF视觉模拟量表（MF-VAS）、RPE、心理运动警觉性、骑行距离、功率输出、心率和血乳酸。
在第1部分中，与对照相比，认知任务增加了举重诱发的RPE（P = 0.011），增加了MF-VAS（P = 0.002），并改变了情绪（P < 0.001）。条件之间的EMG没有差异。在第2部分中，与对照相比，认知任务增加了RPE（P < 0.001）、MF-VAS（P < 0.001）和精神工作量（P < 0.001），但降低了自行车计时赛的功率（P = 0.032）和距离（P = 0.023）。条件之间的心率和血乳酸没有差异。
由认知负荷单独或与身体负荷混合诱发的MF状态，增加了举重和训练期间的RPE，并损害了随后的自行车骑行表现。
