Cardiorespiratory fitness and cognitive functioning following short-term interventions in chronic stroke survivors with cognitive impairment: a pilot study

Abstract

This study, a quasi-experimental, one-group pretest-post-test design, evaluated the effects on cognitive functioning and cardiorespiratory fitness of 8-week interventions (aerobic exercise alone and aerobic exercise and cognitive training combined) in patients with chronic stroke and cognitive impairment living in the community (participants: n=14, 61.93±9.90 years old, 51.50±38.22 months after stroke, n=7 per intervention group). Cognitive functions and cardiorespiratory fitness were evaluated before and after intervention, and at a 3-month follow-up visit (episodic memory: revised-Hopkins Verbal Learning Test; working memory: Brown-Peterson paradigm; attention omission and commission errors: Continuous Performance Test; cardiorespiratory fitness: peak oxygen uptake during a symptom-limited, graded exercise test performed on a semirecumbent ergometer). Friedman's two-way analysis of variance by ranks evaluated differences in score distributions related to time (for the two groups combined). Post-hoc testing was adjusted for multiple comparisons. Compared with before the intervention, there was a significant reduction in attention errors immediately following the intervention (omission errors: 14.6±21.5 vs. 8±13.9, P=0.01; commission errors: 16.4±6.3 vs. 10.9±7.2, P=0.04), and in part at follow-up (omission errors on follow-up: 3.4±4.3, P=0.03; commission errors on follow-up: 13.2±7.6, P=0.42). These results suggest that attention may improve in chronic stroke survivors with cognitive impairment following short-term training that includes an aerobic component, without a change in cardiorespiratory fitness. Randomized-controlled studies are required to confirm these findings.

The Effectiveness of Exercise on Cognitive Performance in Individuals with Known Vascular Disease: A Systematic Review

“…(1) Aerobic Exercise Training: In total, five investigations examined the effects of an aerobic exercise intervention on memory and cognition in individuals with CBVD against a similar control group [43,44,45,55,59]. The frequency of exercise sessions ranged from 2 to 3 times per week, while intensity varied widely and ranged from moderate to high at 40–80% HRR, with the majority of studies utilizing 70% HRmax.…”

“…The shorter duration studies investigated 8 weeks of aerobic exercise training and reported significant improvements in cognitive function in older individuals with CBVD [43,44,45,55]. El-Tamawy et al (2012) and El-Tamawy et al (2014) conducted similar aerobic exercise interventions in post-ischemic stroke participants and found that 45-minute of continuous exercise on a stationary bicycle, 3 times per week, resulted in not only improved attention, memory, and visuospatial abilities, but also increased serum BDNF levels [43] and CBF in the MCA [44].…”

“…Despite only finding modest improvements in fitness, increases in information processing speed and attention were found following the exercise intervention [45]. In a more recent study, Blanchet et al (2016) demonstrated improvements in attention following 30-minute sessions of aerobic exercise at 60–70% HRmax, twice a week, that were retained at 3-months follow up [55]. Although this trial found no improvement in fitness or episodic memory function after the intervention, levels did not decline from baseline when measured immediately after the 8-week intervention and at 3-months follow up [55].…”

“…In a more recent study, Blanchet et al (2016) demonstrated improvements in attention following 30-minute sessions of aerobic exercise at 60–70% HRmax, twice a week, that were retained at 3-months follow up [55]. Although this trial found no improvement in fitness or episodic memory function after the intervention, levels did not decline from baseline when measured immediately after the 8-week intervention and at 3-months follow up [55]. Taken together, the findings of these four studies highlight the efficacy of aerobic exercise intervention on improving various domains of cognitive function in older individuals with CBVD, even over a short duration of time.…”

Synergistic effects of aerobic exercise and cognitive training on cognition, physiological markers, daily function, and quality of life in stroke survivors with cognitive decline: study protocol for a randomized controlled trial

“…Post-stroke cognitive impairment and rehabilitation have recently been identified as the top research priority for post-stroke survivors [ 5 ]. Current evidence indicates that targeted cognitive rehabilitation after stroke, including exercise training [ 6 – 8 ] or cognitive training [ 9 , 10 ], provides potential means of promoting cognitive function. A recent overview of the evidence for the effectiveness of cognitive rehabilitation for stroke survivors suggests that cognitive training targeting specific cognitive domains has some positive effects [ 11 ].…”