Conditions: Chronic Obstructive Pulmonary Disease
Keywords: exercise; treadmill; cycle ergometer; breathlessness; leg discomfort
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 20
Healthy volunteers: no

Brief summary:
Previous studies suggest that treadmill exercise may be a more relevant exercise stimulus than the cycle ergometer to demonstrate benefits with bronchodilator therapy in patients with COPD. The hypothesis of the study is that patients with COPD will exhibit greater improvements in exercise endurance and breathlessness with arformoterol compared with normal saline during treadmill walking than with cycle exercise.

Detailed description:
The study is a randomized trial with crossover of consecutively recruited patients with symptomatic COPD. Each patient will participate in seven visits over a 3-4 week period. At the first visit patients will provide informed consent and then be familiarized with equipment and testing protocols. At visits 2 and 3 patients will inhale 2 puffs of albuterol HFA MDI, and then perform symptom limited incremental exercise on the treadmill or cycle ergometer (randomized order); after a one hour rest, the patient will perform constant work exercise at 80-85% of peak VO2 on the same exercise mode.

At visits 4 - 7, patients will perform PFTs at baseline and at 30 and 120 minutes after inhaling arformoterol or normal saline (randomized order) and then constant work exercise on the treadmill or cycle ergometer (randomized order). Metabolic measurements will be made throughout exercise, and patients will provide continuous ratings of breathlessness and leg discomfort using a system consisting of a computer, monitor, and a mouse.

Arms:
arm 1: Bronchodilator therapy with arformoterol solution 15 mcg arm 2: Placebo using normal saline

Interventions: intervention 1: Arformoterol tartrate intervention 2: Placebo: Normal Saline intervention 3: Treadmill Exercise intervention 4: Cycle Exercise
Intervention descriptions: intervention 1: 15 mcg in two ml solution administered via nebulizer intervention 2: Normal saline was nebulized. intervention 3: None intervention 4: None

Protocol document: