Tailored Exercise Training Study Among Adults With HFpEF

Inclusion Criteria: 1. Age\>= 18 yrs 2. LVEF (Left Ventricular Ejection Fraction) \>= 50% 3. History of HFpEF or at risk of HFpEF 1. HFpEF diagnosis based on:- -HF hospitalization within 12 months- * NT-proBNP \>360 pg/mL 2. Risk of HFpEF based on:- * \>2 risk factors (h/o diabetes, hypertension, obesity, physical inactivity by self-report) 4. SPPB \< 10 or VO2\<60th percentile 5. BMI \>=28 (for randomization in phase II) 6. Able to use cell phone and mobile application Exclusion Criteria: 1. Hospitalization 1 month prior to baseline visit 2. History of recurrent falls 3. eGFR (Estimated Glomerular Filtration Rate) \<20ml/min/1.73m 4. Active changes in HF therapies over 2 weeks prior to baseline visit 5. Inability participate in exercise training therapy 6. Inability to perform CPET (Cardiopulmonary Exercise Testing) testing 7. Severe left side valvular heart disease 8. End stage pulmonary disease, requiring continuous supplemental oxygen 9. Major surgery within 3 months of screening or major elective surgery during the duration of the study. 10. Unstable weight defined by \>5% change in body weight in last 30 days before first study visit. 11. Pregnancy