A pilot study on the motivational effects of an internet-delivered physical activity behaviour change programme in Nova Scotian cancer survivors.

Objective: To examine the effects of an internet-delivered, distance-based physical activity (PA) behaviour change programme on motivation to perform PA in cancer survivors.

Design: Breast, prostate and colorectal cancer survivors (N = 95) were randomized to either an online Theory of Planned Behaviour (TPB)-based PA behaviour change programme (UCAN) or usual care.

Main Outcome Measures: Motivational variables from the TPB including intention, planning, attitude, subjective norm, perceived behavioural control and underlying beliefs.

Results: UCAN had significant negative effects on self-efficacy (-.7; 95% CI = -1.2 to -.1; d = -.53, p = .019), affective attitude (-.4; 95% CI = -.8 to -.0; d = -.45, p = .044), instrumental attitude (-.5; 95% CI = -.9 to -.1; d = -.43, p = .026) and confidence to perform PA in bad weather (-.8; 95% CI = -1.6 to -.1; d = -.49, p = .030), despite health issues (-.7; 95% CI = -1.3 to -.1; d = -.48, p = .031), despite pain/soreness (-.7; 95% CI = -1.4 to -.1; d = -.52, p = .020), despite family responsibilities (-1.0; 95% CI = -1.7 to -.3; d = -.62, p = .005) and when PA is boring (-.8; 95% CI = -1.4 to -.1; d = -.54, p = .016).

Conclusion: UCAN had negative effects on motivational variables in cancer survivors. These findings may be explained by methodological issues related to measuring motivation and/or the absence of post-intentional constructs.