What are the effects of acute exercise and exercise training on cerebrovascular hemodynamics following stroke? A systematic review and meta-analysis

Abstract

Introduction. Limited data exist regarding the effects of acute exercise and exercise training on cerebrovascular hemodynamic variables post-stroke. Purpose. This systematic review and meta-analysis 1) examined the effects of acute exercise and exercise training on cerebrovascular hemodynamic variables reported in the stroke exercise literature; and 2) synthesized the peak middle cerebral artery blood velocity (MCAv) achieved during an acute bout of moderate-intensity exercise in individuals post-stroke. Methods. Six databases (MEDLINE, EMBASE, Web of Science, CINAHL, PsycINFO, AMED) were searched from inception to December 1st 2021, for studies that examined the effect of acute exercise or exercise training on cerebrovascular hemodynamics in adults post-stroke. Two reviewers conducted title and abstract screening, full-text evaluation, data extraction, and quality appraisal. Random effects models were used in meta-analysis. Results. Nine studies, including 4 acute exercise (n=61) and 5 exercise training studies (n=193), were included. Meta-analyses were not statistically feasible for several cerebrovascular hemodynamic variables. Descriptive analysis reveals that exercise training may increase cerebral blood flow and cerebrovascular reactivity to carbon dioxide among individuals post-stroke. Meta-analysis of three acute exercise studies revealed no significant changes in MCAv during acute moderate intensity exercise (n=48 participants, mean difference = 5.2 cm/s, 95% CI [-0.6, 11.0], P=0.08) compared to resting MCAv values. Conclusion. This review suggests that individuals post-stroke may have attenuated cerebrovascular hemodynamics as measured by the MCAv during acute moderate-intensity exercise. Higher quality research utilizing agreed upon hemodynamic variables are needed to synthesize the effects of exercise training on cerebrovascular hemodynamics post-stroke.

Aerobic exercise interventions for promoting cardiovascular health and mobility after stroke: a systematic review with Bayesian network meta-analysis

“…HIIT can also elicit acute increases in novel arterial biomarkers, including insulin-like growth factor one and vascular endothelial growth factor, compared with MICT 110 111. While preliminary, this research highlights the potential for HIIT to elicit superior central cardiovascular adaptations compared with MICT after stroke and emphasises emerging areas of vascular research regarding the potential effects of exercise for improving novel cardiovascular and cerebrovascular biomarkers after stroke 112…”

“…110 111 While preliminary, this research highlights the potential for HIIT to elicit superior central cardiovascular adaptations compared with MICT after stroke and emphasises emerging areas of vascular research regarding the potential effects of exercise for improving novel cardiovascular and cerebrovascular biomarkers after stroke. 112 Arterial hypertension is widely regarded as the most important modifiable cardiovascular risk factor for stroke; identifying effective non-pharmaceutical interventions, such as exercise, which can reduce SBP after stroke is particularly important. 3 In the present NMA, we found that HIIT and HICT may reduce blood pressure by up to 7 mm Hg when compared with usual care and non-exercise interventions.…”

Lower middle cerebral artery blood velocity during low-volume high-intensity interval exercise in chronic stroke

“…To address the gap in knowledge, the aim of this study was to characterize the mean middle cerebral artery blood velocity (MCAv), a surrogate measure of cerebral blood flow, 1,3,5,25,[28][29][30] to a single bout of low-volume HIIE in individuals with chronic stroke compared to age-and sex-matched controls (CON). We hypothesized that individuals post-stroke would have lower MCAv: 1) during an acute 10-minute bout of low-volume HIIE, 2) immediately following HIIE, and 3) 30 minutes after HIIE, compared to CON.…”

Reduced Middle Cerebral Artery Blood Velocity Response during Low-Volume High-Intensity Interval Exercise in Chronic Stroke

“…6,13 HIIT may reveal a unique MCAv response in individuals post-stroke due to the repetitive fluctuations in MAP and P ET CO 2 . 9,10,12,14 However, no studies have examined the physiologic response in individuals post-stroke during an acute bout of low-volume HIIT. 14 To address the gap in knowledge, we characterized the MCAv response to a single bout of low-volume HIIT in individuals with chronic stroke compared to age-and sex-matched controls (CON).…”

“…9,10,12,14 However, no studies have examined the physiologic response in individuals post-stroke during an acute bout of low-volume HIIT. 14 To address the gap in knowledge, we characterized the MCAv response to a single bout of low-volume HIIT in individuals with chronic stroke compared to age-and sex-matched controls (CON). We hypothesized that individuals post-stroke would have a reduced MCAv response during HIIT, immediately following HIIT and 30 minutes after HIIT when compared to CON.…”