For years, sports science has operated on the assumption that engaging in a demanding mental task impairs athletic performance. Now, a series of studies led by Darías Holgado—a PhD graduate from the University of Granada (UGR) and researcher at UniDistance Suisse—in collaboration with Daniel Sanabria, a scientist at the Mind, Brain and Behavior Research Center at UGR, confirm that, contrary to popular belief, prior cognitive effort does not negatively affect physical exertion physiology, perceived exertion or athletic performance.
More Than "Fatigue": A Complex Experience
In their most recent experimental study, Holgado and Sanabria discovered something interesting: "Although study participants do report feeling mentally tired after completing a cognitively demanding task, the experience cannot be reduced to simply feeling fatigued. While making mental effort, individuals display a shifting blend of psychological states, such as boredom, focus, effort, frustration or mind-wandering. These states fluctuate over time and differ from person to person," the scientists explain.
Previous scientific literature indicates that following a mental task (and the control condition), participants are typically asked only about their fatigue levels. Consequently, as Holgado and Sanabria point out, "we might be dealing with a case of a 'self-fulfilling prophecy': the hypothesis assumes mental effort causes exhaustion; when asked about fatigue after a demanding task, the participant reports feeling mentally tired; ergo, any subsequent effect measured is attributed to that mental depletion."
"However, performance can also be influenced by other factors like motivation, boredom or frustration. In other words, performing a cognitive task induces multiple psychological states that exert an influence well beyond the potential effect of fatigue," state Darías Holgado and Daniel Sanabria.
The researchers propose that future studies adopt a broader approach to understand how mental tasks impact individual experience as they occur. Rather than focusing solely on fatigue, they suggest analyzing the various psychological experiences that emerge during these activities in greater detail.
The authors believe this shift in perspective could have significant implications for research in psychology, sports and human performance. "After all, the human mind rarely functions as simply as we think," the UGR scientists conclude.
References
Holgado, D., Cailleux, A., Ruggeri, P., Martarelli, C., Bekinschtein, T. A., Sanabria, D., & Place, N. (2025). Individualized Cognitive Effort to Failure Does Not Impact Subsequent Strenuous Physical Performance. Medicine & Science in Sports & Exercise, 57(7), 1603–1615. https://doi.org/10.1249/MSS.0000000000003669
Holgado, D., Sanabria, D., & Place, N. (2026). Do All Paths Lead to Mental Fatigue or Is It Merely a Self-Fulfilling Prophecy? Sports Medicine. https://doi.org/10.1007/s40279-026-02400-z
Holgado, D., Troya, E., Perales, J. C., Vadillo, M. A., & Sanabria, D. (2021). Does mental fatigue impair physical performance? A replication study. European Journal of Sport Science, 21(5), 762-770.
Holgado, D., Sanabria, D., Perales, J. C., & Vadillo, M. A. (2020). Mental Fatigue Might Be Not So Bad for Exercise Performance After All: A Systematic Review and Bias-Sensitive Meta-Analysis. Journal of Cognition, 3(1), Article https://doi.org/10.5334/joc.126
Holgado, D., Jolidon, L., Borragán, G., Sanabria, D., & Place, N. (2023). Individualized Mental Fatigue Does Not Impact Neuromuscular Function and Exercise Performance. Medicine and Science in Sports and Exercise, 55(10), 1823-1834.
Contact
Daniel Sanabria Lucena - @email