High-intensity Exercise After Treatment

This pilot study tests the feasibility and preliminary efficacy of an 8-week, 3-arm pilot exercise trial in which 45 breast cancer survivors will be randomized to high-intensity interval training (HIIT; n=15), moderate-intensity aerobic training (MOD; n=15), or Usual Care (UC; n=15).

Aim 1: Determine the feasibility and acceptability of an 8-week high-intensity interval training (HIIT) program compared with a standard moderate-intensity aerobic training (MOD) program in 45 breast cancer survivors prescribed aromatase inhibitors.

Aim 2: Calculate effect sizes associated with the 8-week HIIT program, compared with MOD and Usual Care (UC), on cognitive and cardiovascular functions in 45 breast cancer survivors.

Eligible individuals will be women diagnosed with Stages I-IIIa breast cancer, have completed primary treatment (i.e., surgery, chemotherapy, and/or radiation therapy), and currently prescribed an aromatase inhibitor. The specific aims are: 1) Determine the feasibility and acceptability of an 8-week high-intensity interval training (HIIT) program compared with a standard moderate-intensity (MOD) program; and 2) Calculate effect sizes associated with the 8-week HIIT program, compared with MOD and usual care (UC), on cognitive and cardiovascular functions. Cognitive function is operationalized as performance on executive function and working memory tasks. Cardiovascular function is operationalized as exercise capacity (VO2peak, heart rate recovery), resting function (heart rate, blood pressure), and cardiovascular structure/function (arterial stiffness, arterial wall thickness, endothelial function). Associations between change in cardiovascular outcomes and change in cognitive outcomes across the intervention period will also be explored.

Eligibility Criteria:
Inclusion Criteria:

* Adult female (aged 19 or older)
* First, primary diagnosis of Stage I-IIIa breast cancer
* Hormone receptor positive (ER+ and/or PR+) diagnosis
* Human epidermal growth factor receptor 2 negative (HER2-) diagnosis
* Completed primary adjuvant treatment (i.e., surgery, chemotherapy, and/or radiation therapy)
* Currently prescribed an aromatase inhibitor
* No evidence of possible cognitive impairment as assessed using the Telephone Interview of Cognitive Status (TICS-M; score \>21)
* Sedentary except for casual lifestyle recreation. This is defined as self-reporting 20+ minutes of exercise physical activity on 2 or fewer days per week within the previous six months.
* Receive physician's clearance to participate in an exercise program
* Agree to be randomized
* Fully vaccinated for COVID-19 ≥2 weeks prior to participation
* Provide written informed consent to participate in study

Exclusion Criteria:

* Males.
* Stage 0 breast cancer diagnosis or metastatic disease
* Currently receiving chemotherapy or radiation therapy for any cancer
* Scheduled to receive breast surgery (e.g., mastectomy, reconstructive surgery) during the study period
* Second cancer diagnosis (excluding non-invasive skin cancers; including breast cancer recurrence)
* Self-report an 20+ minutes of exercise physical activity on 3+ days per week for the previous 6 months
* Pregnant or plan to become pregnant during study period.
* Is not cleared to participate in exercise by a physician.
* Enrolled in another physical activity program
* Unable to cycle on a stationary bike
* Unwilling to complete study requirements
* History of stroke, transient ischemic attack, other neurological disorders, or brain surgery involving tissue removal
* Clinically significant TICS-M score (\<21) during baseline procedures
* Not fully vaccinated for COVID-19