Introduction This study aimed to determine whether a 6-week behaviour change intervention was more effective than a sham intervention for reducing sedentary behaviour (SB) in people with chronic obstructive pulmonary disease (COPD).

Methods People with stable COPD on the waitlist for entry into pulmonary rehabilitation were recruited to this multicentre trial with randomisation (independent, concealed allocation) to either an intervention group or sham group, assessor blinding and intention-to-treat (ITT) analysis. The behaviour change intervention consisted of once weekly sessions for 6 weeks with a physiotherapist to reduce SB through education, guided goals setting and real-time feedback on SB. The sham intervention consisted of once weekly phone calls for 6 weeks to monitor health status. SB was measured continuously over 7 days using thigh-worn accelerometry (activPAL3 micro). The primary outcome was time spent in SB. Participants with at least 4 days of ≥10 hours waking wear time were included in the ITT analysis and those who reported achieving ≥70% of goals to reduce SB or who completed all sham calls were included in a per-protocol analysis.

Results 70 participants were recruited and 65 completed the study (mean±SD age 74±9 years, mean FEV₁ 55%±19% predicted, 49% male). At 6 weeks, no between-group differences in time spent in SB were observed in the ITT analysis (mean difference 5 min/day, 95% CI −38 to 48) or per-protocol analysis (−16 min/day, 95% CI −80 to 48).

Discussion A 6-week behaviour change intervention did not reduce time in SB compared with a sham intervention in people with stable moderate-to-severe COPD prior to pulmonary rehabilitation.