Inspiratory Muscle Training in Obese Breast Cancer Survivors

Study Overview
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Brief Summary
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The investigators propose a randomized controlled trial to determine the effectiveness of inspiratory muscle training in improving exercise tolerance among stage 0-III obese breast cancer survivors.

Detailed Description
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Randomized controlled trial (RCT) where obese participants (N=133) are randomized to 2 arms: [i] IMT 4 wks + Exercise 12 wks, [ii] SHAM 4 wks + Exercise 12 wks).

Official Title
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Reducing Exercise Intolerance Through Inspiratory Muscle Training in Obese Breast Cancer

Conditions
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Cancer Survivors, Obesity, Breast Cancer

Intervention / Treatment
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* Behavioral: Inspiratory muscle training
* Behavioral: Exercise training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: completed active treatment for a Stage 0-III breast cancer diagnosis within 6 months to 5 years of enrollment. obese as defined by a body mass index (BMI) of 30 to 50 kg/m2 patients who are on adjuvant endocrine therapy will be allowed to participate. sedentary (participating in less than 90 min of moderate intensity activity per week) and have at least one limitation in activity on the 10-question RAND-36 Physical Function Subscale to ensure some exercise intolerance Exclusion Criteria: functional limitations that make independent exercise unsafe current smokers metastatic breast cancer ongoing or active infection with recent antibiotics or steroids heart disease precluding exercise (congestive heart failure, unstable angina pectoris, cardiac arrhythmia) psychiatric illness/social situations that would limit compliance with study requirements orthopedic or neuromuscular disorders or arthritis that preclude participation in exercise unwilling or unable to follow protocol requirements pregnant or nursing any condition which in the investigator's opinion deems the subject an unsuitable candidate to participate in this study presence of provokable ECG changes suggestive of heart disease, or dangerous arrhythmias or exercise induced hypertension, etc. during the cardiopulmonary exercise test non-English speaking

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 4 wk IMT + 12 wk exercise<br>4 weeks of IMT, 3/week, 3 sets of 15 repetitions, intensity up to 70% of MIP using a pressure threshold device PLUS 12 weeks of aerobic exercise training including cycling, walking, elliptical, starting in week 5, 3/week, up to 50min per session, moderate intensity | Behavioral: Inspiratory muscle training<br>* Training of respiratory muscles<br>Behavioral: Exercise training<br>* Supervised aerobic exercise intervention<br>|
| Sham Comparator: 4 wk SHAM + 12 wk exercise<br>4 weeks of SHAM training, 3/week, 3 sets of 15 repetitions, intensity up of 10% of MIP using a pressure threshold device PLUS 12 weeks of aerobic exercise training including cycling, walking, elliptical, starting in week 5, 3/week, up to 50min per session, moderate intensity | Behavioral: Exercise training<br>* Supervised aerobic exercise intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in exercise tolerance | Continuous variable assessed as time to exhaustion during a CWRET at 80% of peak work rate. Units: minutes. | Baseline to 4 weeks | 
| Change in exercise tolerance | Continuous variable assessed as time to exhaustion during a CWRET at 80% of peak work rate. Units: minutes. | Baseline to 16 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in inspiratory muscle strength | Continuous variable, Maximal inspiratory pressure. Units: cm H20 | Baseline to 4 weeks | 
| Change in inspiratory muscle strength | Continuous variable, Maximal inspiratory pressure. Units: cm H20 | Baseline to 16 weeks | 
| Change in inspiratory muscle endurance | Continuous variable, Maximal voluntary ventilation in 12 seconds. Units: L/min | Baseline to 4 weeks | 
| Change in inspiratory muscle endurance | Continuous variable, Maximal voluntary ventilation in 12 seconds. Units: L/min | Baseline to 16 weeks | 
| Change in exercise capacity | Continuous variable, peak oxygen uptake. Units: L/min | Baseline to 4 weeks | 
| Change in exercise capacity | Continuous variable, peak oxygen uptake. Units: L/min | Baseline to 16 weeks | 
| Change in dyspnea | Continuous variable, mMRC dyspnea scale score. Units: score 0 to 4 | Baseline to 4 weeks | 
| Change in dyspnea | Continuous variable, mMRC dyspnea scale score. Units: score 0 to 4 | Baseline to 16 weeks | 
| Change in fatigue | Continuous variable, FACIT:F version 4 total score. Units: score 0 to 52 | Baseline to 4 weeks | 
| Change in fatigue | Continuous variable, FACIT:F version 4 total score. Units: score 0 to 52 | Baseline to 16 weeks |