Isolated knee extensor exercise training improves skeletal muscle vasodilation, blood flow, and functional capacity in patients with HFpEF

FIGURE 1. Experimental protocol. Patients with HFpEF (n = 9) completed graded cardiopulmonary exercise testing on a cycle ergometer to determine peak V̇O2, cardiac output (Q̇c) and a‐v O2 difference, and Qc/V̇O2 slope during maximal exercise. Patients also completed assessments of hemodynamics and a leg blood flow during isolated knee extension exercise to quantify vascular function during exercise independent of central cardiac limitations. Patients were then trained for 8 weeks using the IKE method to maximize peripheral adaptations to exercise. At the end of 8 weeks, graded exercise testing and IKE testing were repeated to determine the effect of IKE training on peripheral vascular function and whole‐body functional capacity. HFpEF, heart failure with preserved ejection fraction; IKE, isolated knee extension; UL, unloaded exercise.

FIGURE 2. IKE training improves skeletal muscle vascular function in HFpEF. Change in (a) mean arterial pressure, (b) leg blood flow (femoral artery), and (c) vascular conductance during graded isolated knee extension exercise (IKE) in healthy, sedentary senior controls (N = 9), and HFpEF patients (n = 8) before and after 8 weeks of IKE training. HFpEF, heart failure with preserved ejection fraction; IKE, isolated knee extension. *HFpEF pre vs. Control; †HFpEF post vs. HFpEF pre.

FIGURE 3. (a) IKE training improves functional capacity in HFpEF. V̇O2, (b) Cardiac Output, and (c) a‐vO2 difference during peak cycle exercise in healthy, sedentary, senior controls (n = 9), and HFpEF patients before and after 8 weeks of IKE training. (d) Q̇c/V̇O2 slope during graded cycle exercise testing in controls and HFpEF patients after 8 weeks of IKE training. HFpEF, heart failure with preserved ejection fraction; IKE, isolated knee extension. *HFpEF pre vs. Control; †HFpEF post vs. HFpEF pre.