Rationale, design and baseline characteristics of a randomized controlled trial of a web-based computer-tailored physical activity intervention for adults from Quebec City.

BACKGROUND: The relationship between physical activity and cardiovascular disease (CVD) protection is well documented. Numerous factors (e.g. patient motivation, lack of facilities, physician time constraints) can contribute to poor PA adherence. Web-based computer-tailored interventions offer an innovative way to provide tailored feedback and to empower adults to engage in regular moderate- to vigorous-intensity PA. To describe the rationale, design and content of a web-based computer-tailored PA intervention for Canadian adults enrolled in a randomized controlled trial (RCT). METHODS/DESIGN: 244 men and women aged between 35 and 70 years, without CVD or physical disability, not participating in regular moderate- to vigorous-intensity PA, and familiar with and having access to a computer at home, were recruited from the Quebec City Prospective Urban and Rural Epidemiological (PURE) study centre. Participants were randomized into two study arms: 1) an experimental group receiving the intervention and 2) a waiting list control group. The fully automated web-based computer-tailored PA intervention consists of seven 10- to 15-min sessions over an 8-week period. The theoretical underpinning of the intervention is based on the I-Change Model. The aim of the intervention was to reach a total of 150 min per week of moderate- to vigorous-intensity aerobic PA. DISCUSSION: This study will provide useful information before engaging in a large RCT to assess the long-term participation and maintenance of PA, the potential impact of regular PA on CVD risk factors and the cost-effectiveness of a web-based computer-tailored intervention. TRIAL REGISTRATION: ISRCTN36353353 registered on 24/07/2014.

Using the Theory of Planned Behaviour to predict exercise intention in obese adults.

The purpose of this cross-sectional study was to use Ajzen's Theory of Planned Behaviour (TPB) as a theoretical framework for understanding the intention to be physically active among a group of obese individuals. Individuals (n = 96) classified as obese (BMI > or = 30 kg/m2) completed a self-administered questionnaire assessing intention to be physically active and its theoretically related variables. The TPB explained 66% of the variance in physical activity intentions. Significant independent predictors of intention were perceived behavioural control (beta = .40) and attitude (beta = .36). The consideration of past behaviour (beta = .32) explained an additional 7% of the variance. These findings support the idea that, in designing interventions for obese individuals, nurses should focus on developing skills to overcome barriers to physical activity and on developing a positive attitude towards this behaviour.