The effects of moderate intensity physical activity on cognitive function in a stroke population

Abstract

Introduction
Cognitive impairment after stroke is common. Evidence suggests that aerobic exercise is effective in the improvement of cognitive function after stroke, specifically for domains such as attention, memory, and processing speed. However, the optimal parameters of exercise are unclear. The aim of this programme of research was to determine the optimal parameters of exercise for cognitive function in a stroke population and investigate the feasibility of an exercise intervention that focuses on cognitive improvement.

Methods
Study one was a systematic review and meta-analysis on the effects of exercise intensity and dose on cognitive function after stroke to inform the parameters (e.g., intensity, duration, and dose) of the exercise intervention. Study two was an explorative multi-perspective qualitative study utilising semi-structured online/phone interviews to determine barriers and facilitators to exercise after stroke. The findings from study one and study two informed the design of study three, an eight-week, home-based, dual task, moderate intensity physical exercise and cognition training intervention. Post intervention interviews were conducted to assess feasibility and acceptability.

Results
Study one reported evidence of the beneficial effects of aerobic exercise for cognitive functioning after stroke. The findings suggested that moderate intensity exercise may promote the greatest cognitive improvements, although duration is also a key factor to consider. Study two identified novel barriers to exercise after stroke including cognitive impairment and the psychological impact of stroke. Facilitators reported include individualised exercise programmes, home-based programmes, group exercise sessions and caregiver exercise training. Study three found that an eight-week, moderate intensity, home-based, dual-task physical exercise and cognitive training programme was feasible and acceptable in a community dwelling stroke population with mild severity.

Conclusions
The home-based intervention delivered in this thesis was considered feasible in a stroke population with mild stroke severity. Based on the findings of this research programme, future research should examine different intensities of exercise within a single study to determine optimal intensity for cognitive improvement. Future research should investigate its suitability in stroke survivors with moderate-severe stroke severity.

Date of Award	Nov 2023
Original language	English
Supervisor	Victoria Simms (Supervisor), Noel Brick (Supervisor), Liz Simpson (Supervisor) & Niamh Kennedy (Supervisor)