RecruitingBehavioural interventionProlonged Overnight Fasting and/or Exercise on Fatigue and Other Patient Reported Outcomes in Women With Hormone Receptor Positive Advanced Breast CancerThe purpose of this study is to test if four different programs (prolonged overnighting fasting alone, exercise alone, a combination of prolonged overnight fasting and exercise, or general health education sessions alone) can reduce fatigue in women with advanced or metastatic breast cancer who are receiving a medication called a cyclin-dependent kinases-4 and 6 (CDK4/6) inhibitor (e.g., palbociclib, ribociclib, or abemaciclib), with or without HER2-directed therapy (e.g., trastuzumab ± pertuzumab), or in combination with both a CDK4/6 inhibitor and a PI3K inhibitor, within the past 90 days.