Associations Between Physical Activity Intensities and Physical Function in Stroke Survivors

Purpose Impairment caused by stroke is a major cause of disablement in older adults. Physical activity has been shown to improve physical functioning; however, little research has been done to explore how physical activity of different intensities may affect physical function among stroke survivors. The purpose of this study was to examine the patterns of accelerometer-measured physical activity and the relationship between physical activity intensities and objective physical functioning and perceived functional limitations in stroke survivors. Methods Stroke survivors (N= 30, mean age = 61.77 +/- 11.17) completed the Short Physical Performance Battery and the Late-Life Function and Disability Instrument. Physical activity intensities were measured objectively using a 7-day actigraph accelerometer wear period and scored using the National Health and Nutrition Examination Survey cutoffs for sedentary (counts/minute <= 100), light (counts/minute 101-2019), and moderate to vigorous (moderate to vigorous physical activity counts/minute >= 2020) activity. Results Multiple linear regressions controlling for age and time since stroke demonstrated that higher levels of moderate to vigorous physical activity predicted better Short Physical Performance Battery performance (beta = .43,P= 0.04). For self-reported physical function, light physical activity predicted better basic lower limb function (beta = .45,P= 0.009), better advanced lower limb function (beta = .53,P= 0.003), better upper limb function (beta = .37,P= 0.04), and higher total function score (beta = .52,P= 0.002) on the Late-Life Function and Disability Instrument. Conclusions These findings suggest that light activity as well as moderate to vigorous physical activity may contribute to better physical functioning in stroke survivors. Although moderate to vigorous physical activity significantly predicted the objective measure of physical function (Short Physical Performance Battery), light physical activity consistently predicted higher scores on all subscales of the Late-Life Function and Disability Instrument. Disabilities resulting from stroke may limit this population from engaging in moderate to vigorous physical activity, and these findings highlight the importance of light physical activity, which may offer similar perceived functional benefits. Future studies should focus on development of effective exercise interventions for stroke survivors by incorporating and comparing both moderate to vigorous physical activity and light-intensity physical activity.