Performance psychology: the power of an uncluttered mind

Implications for athletes

Clearly, mental fatigue can impact performance during high-intensity resistance training. Subjects experiencing mental fatigue were able to complete fewer repetitions than subjects that had not experienced mental fatigue, and this occurred during both upper body and lower body strength exercises.

While the subjects in these studies performed specific demanding cognitive tasks prior to strength training, it’s reasonable to assume that any task requiring sustained cognitive effort will have a similar effect. This could include studying for exams, performing creative work for a job, sustained effort on a work project, or intense focus during important meetings. Of course, these situations don’t just happen during as a result of professional or academic activity. They can and often do happen during one’s personal life as well. The important point however is that in many ways, these mental demands are often unavoidable. The upshot therefore is that training loads must be managed to account for this reality.

Practical advice

While the impact of mental fatigue on performance during resistance training is clearly evident, it’s less obvious what athletes should do about it. However, we can make some recommendations based upon the same principles that govern the management of physical fatigue. The best option is to reduce or eliminate any source of unnecessary mental fatigue, as appropriate. While quitting school, a job, or one’s family isn’t a reasonable option(!), removing any source of avoidable mental fatigue would be very sensible.

The next step would be to plan your intense training sessions for times when you’re experiencing low levels of mental fatigue. For instance, if Monday is a day that consistently requires high levels of focus and engagement outside of sport, planning an intense training session on Monday evening or Tuesday morning makes little sense. In this case, perhaps a Tuesday evening or Wednesday morning session would work better once enough time has elapsed to allow for recovery. Look at your schedule and identify the best opportunities for good training to occur.

Lastly, life is unpredictable and mental fatigue may creep up on days where intense training sessions are scheduled. In this case, two options are available. The first strategy is to complete the session as planned, with modified expectations. If the mind is fatigued, you may not be able to perform optimally - but rather than letting this create frustration, you can simply do what’s possible, while understanding it may not be the best training session. The second strategy is to take the day off or perform a lighter session, moving the more intense session back a day. This provides the best opportunity to perform when optimally ready.

Although not specifically reviewed, the results of this study likely extend beyond resistance training to include any type of high-intensity exercise. Therefore, although speculative, similar outcomes of mental fatigue-induced performance losses could be expected with sprinting, intense interval training, or any other intense mode of training. The commonality between all of these activities is that they require high levels of focus and exertion, both of which are likely compromised by mental fatigue. As such, the same strategies described above will likely be useful for those engaging in these activities, whether they experience mental fatigue in an on-going basis or intermittently.

In summary

The bottom line is that mental fatigue compromises our ability to perform as does physical fatigue. Failure to appreciate this reality could leave you consistently underperforming in training, which will lead to competitive underperformance over time. Athletes should therefore strive to reduce and recover from mental fatigue, and when possible, plan their training schedule to account for the mental fatigue they experience in everyday life, and adjust their training schedule when mental fatigue presents itself unexpectedly. Doing so will lead to better training sessions and better performance over time.

References

1. Sci Med Footb. 2021 May;5(2):150-157
2. Exp Physiol. 2021 Dec;106(12):2294-2298
3. Motor Control. 2022 Dec 12;1-20. doi: 10.1123/mc.2022-0051. Online ahead of print