Outdoor Walking Training Compared To Cycle Ergometer Training in Severe COPD: A Randomized Controlled Feasibility Trial

Abstract

Exercise can improve walking capacity in persons with chronic obstructive pulmonary disease (COPD). However, most endurance training programs use cycle ergometers. The objectives of this study were: (i) to evaluate the feasibility of a randomized controlled trial (RCT) comparing outdoor walking training (OWT) to cycle ergometer training (CT) during inpatient rehabilitation in persons with severe COPD; (ii) to estimate the effect of OWT and CT on health-related quality of life, physical capacity and physical activity; and (iii) to estimate the required sample size for a RCT. A single-blind randomized controlled feasibility trial was conducted with three months' follow-up in the rehabilitation center in Walenstadtberg, Switzerland. Sixteen patients were included in the study, which had a recruitment rate of 33% (16/48). Patients were allocated to an OWT (n = 8) or CT (n = 8) group. Participants completed 75% of scheduled training and the follow-up rate was 75%. All participants in the OWT group were satisfied with the training. The OWT group had better health-related quality of life after three weeks' training compared to the CT group (p = 0.042, 95% confidence interval (95% CI) 1.06–49.94, effect size (d)=1.19). No exacerbations occurred in the OWT group, but three occurred in the CT group after three months’ follow-up. There was no significant difference in the other outcomes. In conclusion, the study design and the OWT are feasible. Health-related quality of life improved in the OWT group compared to the CT group after three weeks' inpatient rehabilitation. A minimum of 46 participants is needed for a RCT.

Trial registration: www.who.int/trialsearch DRKS00010977

Keywords:

• Interval training
• physical activity
• quality of life
• exacerbation

Acknowledgments

The authors would like to thank the rehabilitation team at the rehabilitation center Walenstadtberg for their valuable cooperation. Special thanks go to Philippe Merz who made his concept available for this study.

Winner of the ENPHE Master Thesis Award 2017

Declaration of interest statement

The authors state that they have no financial, consulting or personal relationships to people or organizations that could influence the authors' work. There are no conflicts of interests.

Funding

This study was financially supported by Valens Clinics.

Box 1 Feasibility of outdoor walking training (OWT) and study design

Study design

• Adaptations for a future RCT

  • Use a walking test (instead of a cycle ergometer test) to determine HRmax for OWT.

  • Total sample size of 128 patients.

  • Extended recruitment period of three years.

OWT

• All participants performed the training at the determined intensities.

• High compliance rate for the training sessions despite changing weather conditions.

• 70% of the patients in OWT had difficulty handling the heart rate monitor and were instructed to use the modified Borg scale instead.

• It is not possible to classify the patients into performance groups according to the GOLD stages.

• Patients and physiotherapist were satisfied with OWT.

• Patients intended to continue OWT at home.

• Physiotherapists described OWT as effective, feasible and meaningful.

• Low exacerbation rate after three-month follow-up in the OWT: n = 0, CT group: n = 3.

Box 1 shows the feasibility of OWT and the study design. In summary, OWT is feasible in patients with chronic obstructive pulmonary disease (COPD), the study design needs some adaptions for a future RCT. RCT; randomized controlled trial, HR_max; maximal heart rate, OWT; outdoor walking training, GOLD; global initiative for chronic obstructive lung disease, CT; cycle ergometer training