Abstract 18329: Aortic Pulse Wave Velocity Improves Following Moderate-intensity Continuous Training but not High-intensity Interval Training in Older Men and Postmenopausal Women

Abstract

Introduction: Aortic pulse wave velocity (AoPWV), a measure of arterial stiffness, increases with age and is an independent predictor of cardiovascular disease. Higher levels of habitual physical activity are associated with reduced AoPWV, but the effect of well-controlled aerobic training interventions in healthy older adults remains unclear. We hypothesized that moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) will both improve AoPWV in healthy older adults. Methods: Thirty five sedentary older men and postmenopausal women, free of overt cardiovascular disease (age, 65±1 yrs, body mass index, 27.7±0.8 kg/m 2 ; systolic and diastolic blood pressures, 116±2 and 69±1 mmHg, respectively; mean±SE) participated in this intervention. Subjects were randomized to MICT (n=13), HIIT (n=12) or non-exercise control group (CONT; n=10). Isocaloric MICT and HIIT were performed on Airdyne bicycles 4 days/week for 8 weeks under supervision. MICT consisted of 47 min of cycling at 70% of maximal heart rate, while HIIT consisted of 40 min of cycling at alternating intensities of 90% and 70% of maximal heart rate. AoPWV, aortic systolic and diastolic blood pressures were evaluated using applanation tonometry (SphygmoCor) before and after the intervention. Results: AoPWV improved by 0.52 m/s in MICT (9.26±0.39 vs. 8.75±0.35 m/s, pre- vs. post-intervention; P<0.05), but did not change in HIIT (9.29±0.29 vs. 9.16±0.38 m/s, P>0.05) or CONT (8.82±0.75 vs. 9.26±0.70 m/s, P>0.05). Aortic systolic blood pressure (MICT: 106±2 vs. 107±3 mmHg; HIIT: 115±3 vs. 113±4 mmHg; CONT: 109±5 vs. 110±4 mmHg) and diastolic blood pressure (MICT: 69±2 vs. 69±2 mmHg; HIIT: 70±2 vs. 70±2 mmHg; CONT: 68±2 vs. 69±2 mmHg) did not change with the intervention (P>0.05). Body mass index remained unchanged in all groups (P>0.05). Conclusions: MICT Airdyne exercise leads to arterial destiffening, however, HIIT does not lead to improved arterial stiffness in healthy older men and postmenopausal women.