Effects of a training program including downhill walking in COPD: A randomized controlled trial

Background: Development of contractile muscle fatigue (CMF) directly relates to training response in COPD. Downhill walking (DW) induces CMF with less symptoms of dyspnoea and fatigue than conventional level walking (LW). Aim: To compare the effects of LW and DW as part of a 12-week high-intensity pulmonary rehabilitation program in COPD patients. Methods: 34 patients (62±8years; FEV1 50±17%pred) were randomised to complete training with LW or DW. Exercise capacity (6-minute walk test, 6MWT [primary outcome]; cycle endurance test, CET), muscle function and quality of life were assessed before and after program completion. Absolute training change and the proportion of subjects exceeding the 30m minimally important difference (MID) for 6MWT were compared between the two groups. Results: Similar improvements were observed across all outcomes in both groups(Table 1). 94% of patients in DW(n=16) exceeded the 6MWT MID compared to 65%(n=11) in LW(χ 2 test p=0.03). Conclusion: The magnitude of improvement with DW was similar to that of LW across most outcomes in patients with COPD, however a significantly greater proportion of patients exceeded the MID for 6MWT. These results support the use of downhill walking as a useful adjunct in pulmonary rehabilitation programs for patients with COPD. Funding: CAC- CNPq/Brazil (202425/2011–8); CO- ERS (LTRF 2014); HD- ERS/SEPAR (LTRF 2015); TT- FWO/Belgium (G.0871.13).