Zalewski, Paweł, Kujawski, Sławomir, Tudorowska, Malwina et al. · Brain sciences · 2019 · DOI
This study tested whether a 16-week structured exercise program could help improve 'brain fog' and thinking problems that many people with ME/CFS experience. Of 53 patients who started the program, 34 completed it. Tests showed that those who finished the program had modest improvements in attention and processing speed, particularly in how quickly and accurately they could respond to visual tasks.
Cognitive dysfunction ('brain fog') is a hallmark symptom affecting quality of life in ME/CFS patients, yet few studies examine whether structured interventions can improve it. This research provides preliminary evidence that some aspects of cognitive processing may be amenable to exercise-based intervention, though the modest improvements and high dropout rate suggest the approach may only benefit a subset of patients.
This study does not prove that exercise programs are effective for all ME/CFS patients with cognitive dysfunction—notably, 36% of participants could not complete the program. The lack of a control group means improvements cannot be definitively attributed to the exercise program itself rather than placebo effects or natural variation. The small effect sizes and limited domain-specific improvements suggest any benefits are partial and may not translate to meaningful real-world cognitive gains.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
The first block is for the primary paper and is the citation you should use in research work. The atlas-snapshot line only applies if you are specifically referring to this atlas’s reading of the paper on the date shown.
Primary citation
Zalewski, Paweł, Kujawski, Sławomir, Tudorowska, Malwina, Morten, Karl, Tafil-Klawe, Małgorzata, Klawe, Jacek J, et al. (2019). The Impact of a Structured Exercise Programme upon Cognitive Function in Chronic Fatigue Syndrome Patients.. Brain sciences. https://doi.org/10.3390/brainsci10010004
BibTeX
@article{mecfsatlas-zalewski-2019-impact-structured,
author = {Zalewski, Paweł and Kujawski, Sławomir and Tudorowska, Malwina and Morten, Karl and Tafil-Klawe, Małgorzata and Klawe, Jacek J and Strong, James and Estévez-López, Fernando and Murovska, Modra and Newton, Julia L and The European Network On Me/Cfs Euromene},
title = {The Impact of a Structured Exercise Programme upon Cognitive Function in Chronic Fatigue Syndrome Patients.},
journal = {Brain sciences},
year = {2019},
doi = {10.3390/brainsci10010004},
note = {PubMed: 31861543},
url = {https://www.mecfsatlas.com/evidence/zalewski-2019-impact-structured},
}Atlas snapshot reference
ME/CFS Atlas. Generator v1 / Scanner v1.4 / policy v0.1. Accessed 2026-05-30. https://www.mecfsatlas.com/evidence/zalewski-2019-impact-structured
Contribute
Private, reviewed by a human. Not a public comment thread.