Impact of Lifelong Exercise “Dose” on Left Ventricular Compliance and Distensibility

Abstract

Background Sedentary aging has deleterious effects on the cardiovascular system, including decreased left ventricular compliance and distensibility (LVCD). Conversely, Masters level athletes, who train intensively throughout adulthood, retain youthful LVCD. Objectives To test the hypothesis that preservation of LVCD may be possible with moderate lifelong exercise training. Methods Healthy seniors (n = 102) were recruited from predefined populations, screened for lifelong patterns of exercise training, and stratified into 4 groups: “sedentary” (<2 sessions/week); “casual” (2 to 3 sessions/week); “committed” (4 to 5 sessions/week); and “competitive” Masters level athletes (6 to 7 sessions/week). Right heart catheterization and echocardiography were performed while preload was manipulated using lower body negative pressure and rapid saline infusion to define LV pressure–volume relationships and Frank-Starling curves. Results Peak oxygen uptake and LV mass increased with escalating doses of lifelong exercise, with little change in systolic function. At baseline, LV distensibility was greater in committed (21%) and competitive (36%) exercisers than in sedentary subjects. Group LV stiffness constants (sedentary: 0.062 ± 0.039; casual: 0.079 ± 0.052; committed: 0.055 ± 0.033; and competitive: 0.035 ± 0.033) revealed 1) increased stiffness in sedentary subjects compared to competitive athletes, whereas lifelong casual exercise had no effect; and 2) greater compliance in committed” exercisers than in sedentary or casual exercisers. Conclusions Low doses of casual, lifelong exercise do not prevent the decreased compliance and distensibility observed with healthy, sedentary aging. In contrast, 4 to 5 exercise sessions/week throughout adulthood prevent most of these age-related changes. As LV stiffening has been implicated in the pathophysiology of many cardiovascular conditions affecting the elderly, this “dose” of exercise training may have important implications for prevention of cardiovascular disease.

Dose–Response Relationship Between Physical Activity and Risk of Heart Failure

“…47,[49][50][51] Age-related decline in left ventricular compliance and diastolic function has been implicated in the development of HF, particularly HF with preserved ejection fraction. [52][53][54][55] In a recent study, Bhella et al 56 observed that high levels of lifetime exercise (ie, 4-5 times per week) were associated with more favorable left ventricular compliance. In contrast, there Figure 2.…”

“…were no differences in left ventricular compliance between sedentary individuals and casual exercisers (ie, 1-2 times per week). 56 Thus, doses of PA in excess of current guideline recommendations may be required to achieve favorable changes in cardiac structure and function and to lower HF risk.…”

Altered left ventricular performance in aging physically active mice with an ankle sprain injury

“…These molecular factors are likely related to cardiomyocyte hypertrophy, loss of cardiomyocytes with age, and/or increased cardiac fibrosis (Cornelissen et al 2010;Dutta et al 2012). Recently, Bhella et al (Bhella et al 2014) provided insight into how low doses of regular physical activity do not appear to be sufficient to prevent the decreased LV compliance commonly associated with cardiovascular disease. Limiting frequency of regular exercise is difficult with our longitudinal mouse model but does suggest a necessary exercise volume threshold necessary for positive cardiovascular alterations.…”

Exercise and heart failure: an update

“…These data were confirmed in HFpEF: low cardiorespiratory fitness could be not only considered as an early stage marker but also a target for prevention, owing to the impact of exercise training on risk factor profile, on left ventricle structure and function, on myocardial strain pattern, and on vascular stiffness 19. It was calculated that 1 MET improvement in physical activity was associated with 17% reduction of HFpEF risk at a later age21 and that daily dynamic exercise for >30 min four or five times weekly over the course of a lifetime preserves left ventricle diastolic function 22…”