Response Heterogeneity With Exercise Training and Physical Activity Interventions Among Persons With Multiple Sclerosis.

This was a narrative review and argument paper, not a formal systematic review. It included only studies that reported individual participant data or change scores, so it did not cover all exercise and physical activity studies in multiple sclerosis. Some values were extracted from figures with software, which may differ slightly from the original study data. Many of the reviewed studies had small samples that were poorly characterised, so they provide limited information about individual responses. The review describes variability but does not show which factors cause it or how to predict it for a particular patient.

The authors reported no competing interests. The paper is listed as supported by NIH extramural research funding.

Do not conclude from this review that exercise or physical activity programmes are ineffective for people with multiple sclerosis. The paper reports average benefits in reviewed studies, but it also shows that individual responses vary, including declines, so it argues for more individualised evaluation rather than abandoning exercise.