Feasibility of Fasting & Exercise in Pts With HR+ MBC

This is single-arm feasibility pilot study exploring whether a combined prolonged nightly fasting (POF) and exercise program could impact hyperglycemia and other adverse metabolic consequences of PI3 kinase inhibitors in women with metastatic breast cancer (MBC). Women who exercise regularly and who have lower levels of blood sugar and metabolic hormones like insulin have a lower risk of developing breast cancer. Some evidence also suggests that exercise and metabolism are related to cancer recurrence in women who are diagnosed with breast cancers that can be removed with surgery, but less is known about how exercise and metabolic factors are related to cancer progression in women whose cancer has advanced beyond the breast and underarm lymph nodes. This study is designed to look at the effects of exercise combined with prolonged nightly fasting (having a longer time between dinner and breakfast the next day), on blood sugar and hormones that control metabolism. This study looks to provide important information about whether making these kinds of changes is possible for women living with advanced breast cancer and will explore how making these changes effects blood sugar and hormone levels in women taking different kinds of treatments for advanced breast cancer. The research study procedures include screening for eligibility, a baseline visit to collect information about diet and exercise habits, a baseline blood draw, participation in a 12-week diet and exercise program, and a follow up visit and blood collection at the end of the diet and exercise program. Participants will be in this research study for up to 14-weeks, including the baseline and end of study visits to collect study measures. It is expected that about 30 people will take part in this research study