Arm elevation and coordinated breathing strategies in patients with COPD.
BACKGROUND
Hyperinflated patients with COPD breathe against an increased elastic load during physical activity. Arm activities are especially demanding. Some pulmonary rehabilitation programs instruct patients to inhale while raising their arms, whereas others recommend the opposite. This study aimed to determine the effect of coordinating breathing with arm movements on the endurance of a lifting task.


METHODS
Participants with COPD and hyperinflation completed two (high intensity and severe intensity) rhythmic, constant load-lifting tasks to intolerance (tlimit) before and after attending four "teaching" sessions. Participants were randomly assigned to one of three groups: (1) taught to inhale during the lift, (2) taught to exhale during the lift, or (3) sham (unconstrained coordination).


RESULTS
Thirty-six participants (FEV1 % predicted [SD], 34 [13]; FEV1/FVC [SD], 33% [10%]; thoracic gas volume % predicted [SD], 179 [44]) completed the study. There was an effect of group on the change in tlimit (P<.01) regardless of task intensity (P=.47). The change in tlimit in the exhalation group was greater than in both the sham (difference [95% CI]: 2.82 [0.21-5.44] min; P<.05) and inhalation (difference [95% CI]: 3.29 [0.65-5.92] min; P<.05) groups at the high intensity. There was no difference in the change in tlimit between the inhalation and sham groups.


CONCLUSIONS
A specific breathing strategy, exhalation during the lift, improved task performance. Coordinating exhalation with lifting may be of value to hyperinflated patients with COPD who are engaged in arm and shoulder training exercises or daily activities that involve arm elevation.


TRIAL REGISTRY
ClinicalTrials.gov; No: NCT00836108; URL: www.clinicaltrials.gov.