LONG-TERM BENEFITS OF A TAILORED STRENGTH TRAINING INTERVENTION ON ARM FUNCTION IN CHRONIC STROKE SURVIVORS: A FOLLOW-UP STUDY

TL;DR

Tailoring strength training to brain pathway integrity improves and maintains arm function in stroke survivors for up to one year.

Contribution

Demonstrated that tailoring training intensity based on MEPs leads to sustained arm function improvements in chronic stroke survivors.

Findings

Low-intensity training group showed greater and more sustained improvements in arm function.

Function gains were maintained for up to one year post-intervention.

MEP size influenced responses to strength training in stroke survivors.

Abstract

We showed that a tailored strengthening intervention based on the size of motor evoked potentials (MEPs) in the affected arm was effective in improving function in chronic stroke survivors. Here, we investigated whether the short-term gains in arm function were maintained at 1-year follow-up.

Twenty-five participants at the chronic stage of a stroke.

Participants were classified in the light (LI; MEPs 50–120 μV, n = 8) and high (HI; MEPs > 120μV, n = 17) intensity training groups. The strengthening protocol consisted of adjusted exercises for the affected arm (3X/week; 4 weeks). The Fugl-Meyer Stroke Assessment (FMA), Grip strength (GS) and Box and Block test (BBT) were assessed at baseline, post-intervention and at 1-year follow-up. Changes in clinical measures were compared using repeated-measures ANOVA.

A significant effect of time was noted on all outcome measures [FMA: p < 0.001; BBT: p = 0.05; GS: p < 0.001], but the LI group improved more on the FMA (p = 0.003) and maintained their gains at 1-year follow-up (p = 0.527) than the HI group.

The size of MEPs in the affected arm could be a significant factor in influencing responses to strengthening exercises post-stroke and allow gains to be maintained up to 1 year post-intervention.

Following a stroke, adjusting a training program on the integrity of the brain’s motor pathway allowing arm movement translates into short-term gains in arm function. The aim of this study was to assess whether the gains observed were maintained for up to 1 year following training. Thus, 25 participants were assigned to a low or a high-intensity training group, depending on the integrity of their brain’s motor pathway. Each participant trained his affected arm 3/X a week for 4 weeks. Function of the affected arm was assessed before and after training as well as 1 year following the end of the training. Results showed that training allowed significant gains in arm function, but the participants in the low-intensity training group improved better. Adjusting a training protocol to each individual’s integrity of his brain’s motor pathway allows for gain in arm function that is maintained up to 1 year post-training.

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