Inspiratory Muscle Training in Obese Breast Cancer Survivors

This trial is testing whether inspiratory muscle training (a breathing exercise using a special resistance device) can improve exercise tolerance and fitness in obese breast cancer survivors who are physically inactive and experience exercise intolerance. **You may be eligible if...** - You completed active treatment for Stage 0–III breast cancer within the past 6 months to 5 years - Your BMI is between 30 and 50 kg/m² (classified as obese) - You are currently sedentary (less than 90 minutes of moderate exercise per week) - You have at least some limitation in daily physical activities **You may NOT be eligible if...** - Your breast cancer has spread (metastatic) - You have functional limitations that make independent exercise unsafe - You have heart disease, unstable angina, or dangerous heart rhythm problems - You have a significant orthopedic or nerve condition that prevents exercise - You are pregnant or nursing - You only speak a language other than English Talk to your doctor to see if this trial is right for you.