According to a recent study, individuals who engage in mentally taxing activities are likely to find it harder to go on to perform physical exercise.
The researchers at the University of Birmingham’s School of Sport, Exercise, and Rehabilitation Sciences conducted an experiment on a group of 16 men and women to investigate the impact of cognitive tasks on their physical exertion. The findings revealed that participants who experienced mental fatigue had an increased sense of exertion during exercise.
The findings, published in the International Journal of Sports Physiology and Performance, suggest that taking the effects of mental fatigue into account during training may help athletes perform better.
In light of their findings, the researchers recommend coaches reduce athletes’ exposure to mentally challenging tasks, such as smartphone use, before and during training and competitions. Longer term, they should consider ‘brain endurance training’ to increase resilience to mental fatigue.
Lead author Dr. Chris Ring said: “We know that the brain plays a part in physical performance, but the specific effects of mental fatigue have not been well understood. We know that athletes will often be browsing on their smartphones in rests between competing and training. All of that requires mental effort and our results strongly suggest that athletes and coaches need to better understand the effects of these activities on overall performance.”
During the tests, participants completed a 90-minute mental task which involved identifying letter sequences on a screen. They then completed a series of weight-lifting repetitions. A control group watched neutral videos before taking part in the physical task.
In a second experiment, participants completed a series of resistance training exercises, followed by a 20-minute cycling time trial. They performed cognitive tasks before and between the exercises with a control group again watching a neutral video. After the cognitive tasks participants took an online test to confirm levels of fatigue.
In each experiment, the researchers recorded an increase in perceived exertion – how hard it felt to perform the task – among the mentally fatigued participants. In the second experiment, the researchers also noticed a reduced power in the cycling time trial, and less distance covered among the mentally fatigued participants.
The research team has already started to test the links between mental fatigue and performance among groups of elite athletes in ‘real world’ exercise scenarios.
Reference: “Mental Fatigue: The Cost of Cognitive Loading on Weight Lifting, Resistance Training, and Cycling Performance” by Walter Staiano, Lluis Raimon Salazar Bonet, Marco Romagnoli and Christopher Ring, 9 March 2023, International Journal of Sports Physiology and Performance.