Fatigue Is Associated With Perceived Effort and 2-Dimensional Reach Performance After Stroke.

Background and purpose: Poststroke fatigue (PSF) is prevalent and often manifests as high perceived effort during activities. Little is known about how PSF influences goal-directed reaching after stroke. The purpose of this study was 2-fold (1) to evaluate how perceived effort changed when individuals with stroke performed a reaching task with various demands and (2) to determine whether PSF was associated with perceived effort during reaching and reach performance.

Methods: Thirty-six individuals with chronic stroke performed 2-dimensional reach actions under varied conditions with the more and less affected arms. Perceived effort during reaching was assessed using rating of perceived exertion (RPE) and Paas Mental Effort Rating Scale (MERS). Derived reach kinematics were used to quantify reach performance. The Fatigue Severity Scale (FSS) was administered to assess fatigue severity.

Results: Perceived effort was higher when participants reached with the more affected arm, reached toward far and small targets, and performed memory-guided reaching. Both RPE and MERS significantly correlated with the FSS score (r = 0.50 and 0.35, respectively, P < 0.05). Further, FSS correlated with movement time during the more affected arm reaching (ρ = 0.40, p < 0.05) and reach performance discrepancy between the fast and self-selected speed conditions when participants performed with the less affected arm (ρ = 0.36, P < 0.05). Exploratory analysis revealed that the relationship between fatigue and reach control appeared to be modulated by task demand.

Discussion and conclusions: PSF is associated with perceived effort during reaching and reach performance after stroke. These relationships might offer insights into arm performance in the real world after stroke.

Video abstract: for more insights from the authors Supplemental Digital Content available at http://links.lww.com/JNPT/A476.