Inclined Versus Standard Exercise for COPD Patients

This study is designed to provide information regarding how to improve pulmonary rehabilitation for persons with chronic obstructive pulmonary disease (COPD). Pulmonary rehabilitation is an exercise program for COPD patients that is recommended and benefits some, but not all, patients. The question being studied in this trial is whether during an exercise program, walking on an incline might be better than walking on faster on a flat surface in training muscles so that patients might be less short of breath with exercise.

Objective: The objective of this project is to determine the effect of a pulmonary rehabilitation program that utilizes inclined versus standard exercise to improve breathing and walking for individuals with COPD.

Research Design: Fifty-six patients with COPD (28 in each treatment group: inclined or standard rehabilitation) will be recruited through the VA Nebraska-Western Iowa Health Center clinics. Patients will be randomly assigned to either inclined or standard rehabilitation groups and participate in a 12-week pulmonary rehab program (3 sessions/ week). Potential research subjects will undergo a medical history exam \& pulmonary function test at the Omaha VA, and a maximal cardiopulmonary exercise test (CPET) at the Nebraska Cardiac Pulmonary Rehab Center (Rehab Center). Only those that are cleared for participation by a physician will be enrolled.

Methodology: The study will be conducted at the Omaha VA and the Rehab Center. All subjects will be diagnosed with chronic obstructive pulmonary disease (COPD) with no other significant co-morbidities and screened for eligibility. Up to 108 patients may be consented and screened to achieve target enrollment of 58 subjects.

Enrolled participants will first complete a series of questionnaires that will be used as covariates in the analysis at the Rehab Center then proceed with their first rehab session.

The Q-stress system, connected to the participants while they walk on a treadmill, will be used to monitor participants' cardiovascular responses. The treadmill's speed and incline will be incrementally increased until the participants reach 60% of their maximal heart rate as determined by the CPET. For both the standard treadmill walking and incline walking, the goal is to achieve 30 minutes of walking at the 60% intensity without a break at the end of the 12 weeks. For the standard walking, subjects will walk at their preferred speed, on a 0% level surface of the treadmill. The treadmill speed will be incrementally enhanced by 0.05 meters per second each minute until the participant's heart rate attains 60% of the maximal heart rate recorded during the CPET. With the inclined treadmill walking group, participants will begin walking at a pace 20% below their preferred walking speed on a 2% incline, which will then be elevated by 0.5% each minute. Each session will last up to 50 minutes plus 5 minutes of warm-up and cool-down. After completing a session, interviews and questionnaires will be used to assess comfort, fatigue, and exercise intensity.

Outcome measures from the Q-stress system are respiratory flow pattern, dyspnea, dynamic hyperinflation, LRC ratio, total walking time and metabolic equivalence of task (METs).

Clinical relationship: COPD is a major health concern for the Department of Veterans Affairs. Current pulmonary rehabilitation programs do not consistently improve outcomes. Enhancing the effectiveness of these programs could significantly improve patient outcomes. The investigators hypothesize that inclined walking will reduce respiratory rate, dynamic hyperinflation, and dyspnea, thereby improving exercise capacity and quality of life for these patients. These findings can be incorporated into rehabilitation practices, reducing the disability linked to the disease and enhancing the overall health outcomes for Veterans.

Eligibility Criteria:
Inclusion Criteria:

* Veterans from all sex/gender, race, and ethnicity will be recruited
* All subjects will undergo post-bronchodilator spirometry and be clinically stable
* All subjects must have documented FEV1/FVC ratio of \<0.7, and between 30% to 80% FEV1% predicted
* If subjects have non-qualifying spirometry, they will not be screened further
* Subjects with qualifying spirometry will be screened further
* Potential subjects must have a BMI of less than 35 kg/m2 and must be free from co-morbidities that may affect walking patterns

  * e.g., peripheral arterial disease, diabetes, low back pain

Exclusion Criteria:

* Confounding effects such as neurological, musculoskeletal, or metabolic disease
* Subjects taking medications that alter mood or metabolic demand will be excluded
* All potential subjects must be cleared for participation by a physician after undergoing a cardiopulmonary exercise test
* Require an O2 mask during rest or activity