Accelerometer-Measured Volumes of Moderate-to-Vigorous Physical Activity and Functional Fitness in Older Adults

The objective of this study is to investigate the association between different volumes of accelerometer-measured moderate-to-vigorous physical activity (MVPA) and functional fitness in older adults in a cross-sectional study (n = 242; 66 ± 5 years; 80% women). MVPA was assessed by accelerometer for 1 week. Based on the MVPA recommendations, the participants were classified as: (a) inactive (<50 min/week), (b) somewhat active (50-99 min/week), (c) moderately active (100-149 min/week), and (d) active (≥150 min/week). These groups reflect <33%, 33%-66%, 67%-99%, and ≥100% of the MVPA recommendations, respectively. Functional fitness was assessed by the Senior Fitness Test battery: 6-min walk test (6MWT), timed up and go (TUG), 30-s chair stand test, 30-s arm curl test, chair sit-and-reach test, and back scratch test. In addition to the analysis for each functional fitness test, a total functional fitness score was calculated by the sum of the z scores of all tests. Generalized linear models were used for data analyses (reference: inactive). Compared with the inactive group (n = 59), the somewhat active group (n = 47) had better performance on the 6MWT and TUG (p < .05). The moderately active group (n = 47) had better performance on the 6MWT, TUG, 30-s chair stand test, and the total functional fitness score (p < .05). The active group (n = 89) had better performance on the 6MWT, TUG, 30-s chair stand test, chair sit-and-reach test, and the total functional fitness score (p < .05). Older adults who engaged in higher volumes of MVPA had better performance in more functional fitness components. However, lower than recommended volumes of MVPA (meeting ≥50 min/week) were also associated with greater lower limb functional fitness performance.