Aerobic Exercise as an Adjuvant to Aphasia Therapy: Theory, Preliminary Findings, and Future Directions

Abstract

Purpose: This study investigated whether participation in aerobic exercise enhances the effects of aphasia therapy, and the degree to which basal serum brain-derived neurotropic factor (BDNF) concentrations fluctuate after the beginning of aerobic exercise or stretching activities in individuals with poststroke aphasia.

Methods: The study used a single-subject, multiple-baseline design. Seven individuals with chronic poststroke aphasia participated in 2 Blocks of aphasia therapy: aphasia therapy alone (Block 1), followed by aphasia therapy with the addition of aerobic activity via bicycle ergometer (n = 5) or stretching (n = 2) (Block 2). Serum BDNF concentrations from blood draws were analyzed in 4 participants who exercised and in 1 participant who stretched.

Findings: Three of the five exercise participants demonstrated larger Tau-U effects when aphasia therapy was paired with aerobic exercise, whereas 1 of the 2 stretching participants demonstrated a larger effect size when aphasia therapy was paired with stretching. Group-level comparisons revealed a greater overall increase in effect size in the aerobic exercise group, as indicated by differences in Tau-U weighted means. BDNF data showed that all 4 exercise participants demonstrated a decrease in BDNF concentrations during the first 6 weeks of exercise and an increase in BDNF levels near or at baseline during the last 6 weeks of exercise. The stretching participant did not show the same pattern.

Implications: Additional research is needed to understand the mechanism of effect and to identify the factors that mediate response to exercise interventions, specifically the optimal dose of exercise and timing of language intervention with exercise. ClinicalTrials.gov identifier: NCT01113879.

Keywords: BDNF; aphasia; exercise; therapy.

Conflict of interest statement

CONFLICTS OF INTEREST

The authors have indicated that they have no conflicts of interest with regard to the content of this article.

Copyright © 2018 Elsevier HS Journals, Inc. All rights reserved.

Figures

Figure 1.

Study design, presented as a flowchart to illustrate the activities that occurred over time.

Figure 2.

Picture-naming probe data for E3. Picture-naming probes are presented across baseline, treatment, and post-treatment for Blocks 1 and 2. Infrequently probed pictures were untrained. F/U = follow-up.

Figure 3.

Serum brain-derived neurotropic factor (BDNF) concentrations, by participant. E1, E2, E3, and E5 were exercise participants. S2 was a stretching participant. Baseline is the mean of 2 blood draws that occurred before beginning exercise or stretching. First 6 weeks and last 6 weeks were each means of 2 blood draws that occurred during the beginning and end of the exercise/stretching intervention, respectively.