Abstract

Background: While exercise training elicits substantial health benefits, too few individuals adopt exercise as a health maintenance strategy. Thus, determining if a relatively modest duration of exercise training can lead to sustained benefits years later (legacy effects) is clinically important. The STRRIDE I Reunion revealed legacy effects for cardiorespiratory fitness (CRF) and cardiometabolic risk factors 10 years after exercise intervention. In an older cohort at greater risk of disease development, the STRRIDE-PD Reunion study aims to determine whether prior exercise training–with or without weight loss–elicits legacy health effects. Hypotheses: Those who completed vigorous intensity training will have maintained CRF to the greatest extent, while those who completed a high amount of training will have maintained body composition to the greatest extent. Methods: In STRRIDE-PD, sedentary adults (45-75 y) with prediabetes and overweight/obesity were randomized to one of four 6-month aerobic training groups: 1) low amount/moderate intensity (LM); 2) high amount/moderate intensity (HM); 3) high amount/vigorous intensity (HV); or 4) LM plus diet/weight loss (LMD). Waist circumference (WC), body composition via BODPOD, and CRF (relative peak VO 2 ) were measured at baseline, post-intervention, and Reunion (10 y). Change scores were calculated as Reunion value minus baseline. Two-tailed t -tests determined within-group significance (p<0.05). ANCOVA with baseline values assessed among-group effects. Results: Seventy-three participants (71.3±7.2 y; 64% women; 78% White) returned for the STRRIDE-PD Reunion study. Compared to baseline, all groups either maintained (HM and LMD) or significantly reduced (HV and LM) WC and total body mass. LM, LMD, and HV experienced significant reductions in fat free mass. All groups showed a significant decrease in CRF, ranging from ~10% (LM, LMD, and HV) to 16% (HM). Magnitudes of change were not different among groups. Conclusion: All groups exhibited legacy effects for WC, fat mass, and body mass. Although LM and HV significantly reduced WC and body mass compared to baseline, these changes were coupled with fat free mass reductions. Contrary to STRRIDE I, vigorous intensity participants did not maintain CRF to a greater extent than moderate intensity. These STRRIDE-PD specific findings may indicate aging-related skeletal muscle loss and an accelerated CRF decline for older individuals at increased risk for cardiometabolic disease.