The Newcastle exercise project: A randomised controlled trial of methods to promote physical activity in primary care

OBJECTIVE: To evaluate the effectiveness of combinations of three methods to promote physical activity. DESIGN: Randomised controlled trial. Baseline assessment with post-intervention follow up at 12 weeks and 1 year. SETTING: One urban general practice, 1995-7. Participants: 523 adults aged 40 to 64 years, randomised to four intervention groups and a control group. INTERVENTIONS: Brief (one interview) or intensive (six interviews over 12 weeks) motivational interviewing based on the stages of change model of behaviour change, with or without financial incentive (30 vouchers entitling free access to leisure facilities). MAIN OUTCOME MEASURES: Physical activity score; sessions of moderate and vigorous activity in the preceding four weeks. RESULTS: Response rate was 81% at 12 weeks and 85% at one year. More participants in the intervention group reported increased physical activity scores at 12 weeks than controls (38% v 16%, difference 22%, 95% confidence interval for difference 13% to 32%), with a 55% increase observed in those offered six interviews plus vouchers. Vigorous activity increased in 29% of intervention participants and 11% of controls (difference 18%, 10% to 26%), but differences between the intervention groups were not significant. Short term increases in activity were not sustained, regardless of intensity of intervention. CONCLUSIONS: The most effective intervention for promoting adoption of exercise was the most intensive. Even this did not promote long term adherence to exercise. Brief interventions promoting physical activity that are used by many schemes in the United Kingdom are of questionable effectiveness.