The WHISH-2-Prevent Heart Failure (HF) study is an ancillary study to the Women's Health Initiative Strong and Healthy (WHISH) exercise pragmatic trial. The WHISH-2-Prevent HF trial examines the intervention effect of physical activity (PA) on both incident HF and HF burden (recurrent HF and CVD death in those with HF) in a cost effective manner in elderly women. In addition, it will allow a dose-finding analysis to better understand the type, intensity and frequency of PA that leads to a reduced risk and burden of HF. The focus of the parent WHISH trial is on atherosclerotic cardiovascular disease and not heart failure.

A recently funded large pragmatic PA trial, Women's Health Initiative Strong and Healthy (WHISH) trial based upon two decades of PA intervention experience using enhanced communication and behavioral techniques, has randomized 49,936 elderly women (average age 79) and will evaluate its intervention effect on the risk of atherosclerotic CVD. This translational intervention is aimed at reducing sedentary time and achieving or maintaining aerobic and strength enhancing PA levels currently recommended for cardiovascular benefit. The WHISH-2-Prevent HF, represents the first and largest primary prevention exercise trial ever performed focusing on HF and will examine the intervention effect of PA , on both incident HF and HF burden (recurrent HF and CVD death in those with HF) in a cost effective manner in elderly women. In addition, it will allow a dose-finding analysis to better understand the type, intensity and frequency of PA that leads to a reduced risk and burden of HF.

Aim 1: Test whether older women who are initially free of HF and randomized to a translational PA intervention will reduce the rate of incident HF compared to those not randomized to the translational PA intervention.

H1: Women free of HF randomized to the PA intervention will have reduced rates of incident HF compared to those not randomized.

Aim 2: Test whether older women with and without HF at baseline randomized to a translational PA intervention will reduce the HF burden (number of acute HF hospitalizations and CVD death in those with antecedent HF) compared to those not randomized to the translational PA intervention. H2: Women randomized to the PA intervention will have reduced HF Burden compared to those not randomized

Exploratory Aim 3: Analyze the type, intensity and frequency of physical activity including skeletal muscle strengthening associated with a reduced risk of HF and HF burden in elderly women. H3: Women who have low levels of sedentary behavior by either increasing or maintaining light intensity or moderate intensity physical activity will have reduced rates of HF compared to women who remain sedentary. Those that add skeletal muscle strengthening will have additional benefits.

Inclusion Criteria:

• alive, community dwelling,

Exclusion Criteria:

• Dementia, need walking aide, reside in nursing home

self-identified as post-menopausal women and participate in the women's health initiative study

Within two years of completion of study, de-identified data will be made available via WHI website after approval by the Publications and Presentation committee and data use agreement signed

Participant in intervention arm signed an informed consent umasking the exercise intervention, participants in the control arm have already consented to ongoing outcomes assessment and yearly surveys regarding physical activity and other lifestyle activities