Background
High resting pulse rate (RPR) is often associated with adverse cardiovascular risk. Prior studies show that habitual exercise slows RPR, though most studies have focused primarily on persons younger than 65 years. Our objective was to assess the utility of a long-term physical activity (PA) intervention for reducing RPR in older persons.
Design
Lifestyle Interventions and Independence for Elders Study.
Setting
Community based.
Participants
A total 1,635 persons (67.2% women) aged 70–89 years were randomized to a moderate intensity PA intervention (n=818) or health education-based “successful aging” (SA) intervention (n=817).
Measurements
RPR was recorded at baseline, 6-, 18-, and 30-months. Longitudinal changes in RPR were evaluated between intervention groups using a mixed-effects analysis of covariance model for repeatedly measured outcomes, generating least squares means with standard errors (SE) or 95% confidence intervals (95% CI).
Results
Mean duration of the study was 2.6 years (median, 2.7 years; interquartile range, 2.3–3.1 years). The average effect of the PA intervention on RPR across follow-up visits was statistically significant but clinically small (Average Intervention Difference = 0.84 beats/min; 95% CI 0.17 to 1.51; Paverage =0.01), with the most pronounced effect observed at 18-months (PA: 66.5 [0.32] beats/min, SA: 67.8 [0.32] beats/min, Difference = 1.37 (95% CI 0.48 to 2.26). The relationship became somewhat weaker and was not statistically significant at 30-months. There were no significant differences across several pre-specified subgroups.
Conclusion
A long-term moderate-intensity physical activity program was associated with a small and clinically insignificant slowing of RPR in older persons. Whether physical activity can deliver a beneficial reduction in RPR requires further examination among older adults.