Exercise, Gut Microbiome, and Breast Cancer: Increasing Reach to Underserved Populations

Understanding the impact exercise has on a cancer survivor's gut microbiome can improve the health and well-being of cancer survivors by enhancing treatments targeting the gut microbiome. Although scientific studies support a link between exercise and the gut microbiome, rigorous randomized trials needed to confirm this causal link are limited and usually involve supervised exercise. Hence, this proposal tests feasibility of a home-based, remote-only research protocol that is more accessible to cancer survivors unable to attend supervised exercise including but not limited to rural populations. This study will also determine if exercise effects on the gut microbiome differ by factors such as race.

Forty physically inactive breast cancer survivors will be randomized into 10-week conditions of home-based aerobic exercise training or standard attention control. All participants will be asked to maintain their pre-study diet and attempt to maintain their body weight while participating in the study. Assessments will occur at baseline, week 5 (mid-intervention), and week 10 (post-intervention) by videoconference platform. Study feasibility and changes in the gut microbiome will be assessed.

Eligibility Criteria:
Inclusion Criteria:

* Non-Hispanic white or black women
* Age 18-70 years
* History of breast cancer stage 0, I, II, or III
* ≥1 year post-primary cancer treatment completion
* English speaking
* Ambulates without assistance
* No antibiotics in past 90 days
* Willing to avoid taking probiotics during the study
* Has access to a safe place to perform aerobic exercise (e.g., willing to walk in neighborhood or has gym membership or owns relevant exercise equipment at home, etc.)
* Has access to good internet and WIFI and device capable of videoconferencing (the study has limited resources to loan tablets and hotspots)

Exclusion Criteria:

* Metastatic or recurrent cancer
* Another cancer diagnosis in the past 5 years (not including skin or cervical cancer in situ)
* Unstable angina
* New York Heart Association class II, III, or IV congestive heart failure
* Uncontrolled asthma
* Interstitial lung disease
* Current steroid use
* Told by a physician to only do exercise prescribed by a physician
* Dementia or organic brain syndrome
* Schizophrenia or active psychosis
* Connective tissue or rheumatologic disease
* Participating in \>30 minutes of exercise on ≥3 days/week in the past six months
* Anticipate elective surgery, medication changes or antibiotics during the study
* Contraindication to ≥moderate intensity aerobic exercise
* Physical limitations that prevent engaging in ≥moderate intensity aerobic exercise
* Breastfeeding, pregnant or anticipate pregnancy during the study
* Plan to move residence during the study
* Plan to travel for more than 1 week during the study
* Anticipate trouble attending the weekly study videoconference calls
* History of bariatric surgery
* Body weight greater than 440 lbs
* Any social, psychological, or physical condition that interferes with the participant's ability to complete study activities or unduly increases study risk