Longitudinal analysis of physical function in older adults: The effects of physical inactivity and exercise training

Abstract

Lack of exercise contributes to systemic inflammation and is a major cause of chronic disease. The long-term impact of initiating and sustaining exercise in late life, as opposed to sustaining a sedentary lifestyle, on whole-body health measures such as physical performance is not well known. This is an exploratory study to compare changes in physical performance among older adults initiating exercise late in life versus inactive older adults. Data from two observational cohorts were included in this analysis, representing two activity groups. The Active group cohort comprises older adults (n = 318; age 72.5 ± 7.2 years) enrolled in a supervised exercise program, "Gerofit." The inactive group comprises older adults (n = 146; age 74.5 ± 5.5 years) from the Italian study "Act on Ageing" (AOA) who self-reported being inactive. Participants in both groups completed physical performance battery at baseline and 1-year including: 6-min walk test, 30-s chair stand, and timed up-and-go. Two-sample t-tests measured differences between Gerofit and AOA at baseline and 1-year across all measures. Significant between-group effects were seen for all performance measures (ps = 0.001). The AOA group declined across all measures from baseline to 1 year (range -18% to -24% change). The Gerofit group experienced significant gains in function for all measures (range +10% to +31% change). Older adults who initiated routine, sustained exercise were protected from age-related declines in physical performance, while those who remained sedentary suffered cumulative deficits across strength, aerobic endurance, and mobility. Interventions to reduce sedentary behaviors and increase physical activity are both important to promote multi-system, whole-body health.

Keywords: clinical; cohort; physical activity; physical performance; sedentary.

FIGURE 1

Physical function trajectories over time by cohort. All data shown for the Gerofit cohort are from observed physical performance assessments. Baseline and Year 1 data shown for the AOA cohort are from observed physical performance assessments; Year 2–4 data points are estimates.

FIGURE 2

Physical function trajectories over time by age and cohort. All data shown for the Gerofit cohort are from observed physical performance assessments. Baseline and Year 1 data shown for the AOA cohort are from observed physical performance assessments; Year 2–4 data points are estimates.