Conical-PEP is safe, reduces lung hyperinflation and contributes to improved exercise endurance in patients with COPD: a randomised cross-over trial

J Physiother. 2010;56(1):33-9. doi: 10.1016/s1836-9553(10)70052-7.


Question: Does a new positive expiratory pressure device (conical-PEP) decrease lung hyperinflation during exercise in patients with chronic obstructive pulmonary disease compared to normal breathing? Does it increase the duration of exercise?

Design: A randomised, cross-over trial with concealed allocation.

Participants: Thirteen patients with moderate to severe chronic obstructive pulmonary disease (mean FEV1 61% predicted).

Intervention: THE experimental intervention was conical-PEP breathing with a positive expiratory pressure of 4-20 cmH2O during 30% of 1 RM alternate knee extension exercise at 70% age-predicted HRmax to fatigue. The control intervention was normal breathing.

Outcome measures: Total lung capacity (inspiratory capacity and slow vital capacity), breathlessness, and leg discomfort were measured pre and post exercise. Cardiorespiratory function was measured pre and during the last 30 s of exercise. Duration of exercise was recorded.

Results: After the experimental intervention, inspiratory capacity increased 200 ml (95% CI 0 to 400) and slow vital capacity increased 200 ml (95% CI 0 to 400) more than the control intervention. Participants exercised for 107 s (95% CI -23 to 238) more during the experimental intervention than the control intervention. Conical-PEP breathing during exercise resulted in 6.1 fewer breaths/min (95% CI 1.4 to 10.8) than normal breathing; it did not have any adverse effects on CO2 retention or oxygen saturation.

Conclusion: The novel conical-PEP device decreases lung hyperinflation, is safe to use, and tends to increase the duration of exercise.

Trial registration: NCT00741832.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cross-Over Studies
  • Dyspnea / physiopathology
  • Dyspnea / rehabilitation*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Physical Endurance*
  • Positive-Pressure Respiration / methods*
  • Pulmonary Disease, Chronic Obstructive / physiopathology
  • Pulmonary Disease, Chronic Obstructive / rehabilitation*
  • Respiratory Function Tests
  • Respiratory Muscles / physiopathology
  • Treatment Outcome

Associated data