Associations between physical activity intensity and cognitive performance in older adults with and without stroke

Introduction & Purpose: Stroke remains the third leading cause of acquired disability worldwide. Approximately 60% of stroke survivors face cognitive impairments, which are directly linked to reduced quality of life, increased functional decline and higher mortality risk. Physical activity (PA) is well established as an effective means of delaying cognitive decline in neurologically healthy older adults. Recent evidence indicates that, beyond improving cardiorespiratory fitness, increased physical activity after stroke enhances cognitive performance. However, it is not yet established whether the cognitive benefits of high-intensity PA observed in neurologically healthy older adults are comparable among stroke survivors. The present study investigated the association between PA intensity and cognitive function in individuals with a history of stroke. Methods: Using data from the 2011–2014 National Health and Nutrition Examination Survey (NHANES), we analyzed adults aged 60 and older with valid accelerometer data and complete cognitive assessment. The intensity gradient (IG) was used to quantify the 24-h intensity distribution of PA, while cognition was assessed via the Digit Symbol Substitution Test (DSST), Animal Fluency and CERAD Delayed Recall Test. Survey-weighted linear regression models, adjusted for sociodemographic and cardiometabolic factors, were fitted for each cognitive outcome. Stroke history was included as a predictor along with the IG. Results: Physical activity intensity was positively associated with cognitive performance across all domains. Specifically, higher physical activity intensity was associated with better performance on DSST (β = 10.44 [6.12, 14.75], p