• Age \>=60 years old

• Ejection Fraction \>=45%

• In the hospital setting \>24 hours for the management of acute decompensated heart failure (ADHF), or diagnosed with ADHF after being hospitalized for another reason. ADHF will be confirmed by the site physician, and will be defined according to the Food and Drug Administration (FDA) definition of hospitalized heart failure as a combination of symptoms, signs, and HF-specific medical treatments, and requires that all 4 of the following are met:

‣ At least 1 symptom of HF which has worsened from baseline: a. dyspnea at rest or with exertion; b. exertional fatigue; c. orthopnea; d. paroxysmal nocturnal dyspnea (PND)

⁃ At least 2 of the following signs of HF: a. Pulmonary congestion or edema on physical exam (rales or crackles) or by chest X-ray; b. Elevated jugular venous pressure or central venous pressure \>=10 mm Hg; c. peripheral edema; d. wedge or left ventricular end diastolic pressure \>=15 mmHg; e. rapid weight gain (\>=5 lbs.); f. Increased b-type natriuretic peptide (BNP) (\>=100 pg/ml) or N-terminal prohormone BNP (\>=220pg/ml)

⁃ Change in medical treatment specifically targeting HF, defined as change in dose or initiation of or augmentation of at least 1 of the following therapies: a. diuretics; b. vasodilators; c. other neurohormonal modulating agents, including angiotensinconverting enzyme inhibitors, angiotensin II receptor blockers (with or without neprilysin inhibitor), beta-blockers, aldosterone inhibitors, direct renin inhibitors, or sodium-glucose co-transporter-2 inhibitors

⁃ The primary cause of symptoms and signs is judged by the investigator to be due to HF

• Adequate clinical stability to allow participation in study assessments and the intervention Independent with basic activities of daily living, including the ability to ambulate independently (with or without the use of an assistive device) prior to admission

• Able to walk 4 meters (with or without the use of an assistive device) at the time of enrollment