Exploring Age-related Cognitive Benefits Of Cardiorespiratory Fitness In Older Adults

Global cognition, encompassing memory, executive function, processing speed, and attention, is essential for healthy aging. Cardiorespiratory fitness (CRF) has emerged as a key factor in supporting cognitive health, though its age-specific effects remain underexplored. To address this gap, we investigated the association between CRF and global cognition in older adults, using time-varying effect modeling (TVEM) to identify age ranges where the impact of CRF on global cognition is most pronounced. PURPOSE: To examine the association between CRF and global cognition in older adults, focusing on identifying specific age ranges where cognitive performance differences between higher and lower CRF groups are most prominent. METHODS: Data from 2,311 participants aged 60-79 from the 2011-2014 National Health and Nutrition Examination Survey were analyzed. CRF was estimated using a non-exercise regression equation: VO2 max = 79.9 - (0.39 x age) - (13.7 x gender [0 = male; 1 = female]) - (0.127 x weight [lbs]). Participants were categorized into above- and below-median CRF groups using the 50th percentile as the cutoff. Global cognition was assessed through composite z-scores from three cognitive tests: the CERAD Word Learning subtest, assessing immediate and delayed memory; the Animal Fluency Test, assessing executive function; and the Digit Symbol Substitution Test, assessing processing speed, working memory, and attention. TVEM was applied in SAS (version 9.4) to analyze age-specific associations. RESULTS: Higher CRF was significantly associated with better global cognition, particularly between ages 61 and 66 (p < .05). The largest difference was observed at age 62, where individuals with higher CRF had a mean composite cognition score of 0.40 (95% CI = [0.27, 0.53]), compared to 0.03 (95% CI = [-0.10, 0.16]) in those with lower CRF. Beyond age 66, the cognitive differences between the CRF groups diminished, showing no significant difference. CONCLUSION: This study underscores the role of CRF in supporting cognitive resilience in older adults, particularly within certain age ranges. Enhancing CRF may help delay age-related cognitive decline, offering a promising approach for age-targeted interventions to promote cognitive health.