Author + information
- Michinari Hieda,
- Erin Howden,
- Satyam Sarma,
- Takashi Tarumi,
- Dean Palmer,
- Justin Lawley,
- Christopher Hearon Jr.,
- Ashley Hardin,
- Qi Fu,
- Rong Zhang and
- Benjamin D. Levine
Background: The dynamic Starling mechanism (DSM), the dynamic modulation of stroke volume (SV) due to changes in LV end-diastolic pressure (LVEDP), reflects time-varying ventricular-arterial coupling. The DSM is impaired with aging; however it is not clear how much exercise over a lifetime is necessary to preserve the DSM. Defining this dose-response relationship was the aim of this study.
Methods: Healthy seniors (n = 102) were recruited based on lifelong patterns of exercise training frequency, and stratified into 4 groups: “sedentary (n=27)” (<2 /week); “casual (n=25)” (2 to 3 /week); “committed (n=25)” (4 to 5 /week); and “competitive (n=25)” Masters level athletes (6 to 7 /week) during the previous 25 years. Transfer function analysis between diastolic pulmonary pressure (PAD), a surrogate for breath-by-breath changes in LVEDP (from right heart catheterization), versus SV index was applied to obtain gain and coherence of the DSM.
Results: The DSM gain was significantly greater in committed and competitive exercisers than the more sedentary groups. There was no difference in the coherence which confirms the reliability of the linear transfer function among the 4-groups.
Conclusions: There is a graded, dose-dependent improvement in ventricular-arterial coupling with increasing amounts of regular exercise in healthy older individuals. The optimal “dose” of life-long endurance exercise appears to be at least 4-5 sessions/week or more which appears to prevent the impairment of the DSM with aging.
Moderated Poster Contributions
Prevention Moderated Poster Theater, Poster Hall, Hall C
Saturday, March 18, 2017, 10:15 a.m.-10:25 a.m.
Session Title: Physical Activity and Prevention of Cardiometabolic Disease: Exercise Is Medicine
Abstract Category: 34. Prevention: Rehabilitation
Presentation Number: 1210M-07
- 2017 American College of Cardiology Foundation