Design and rationale for the PREVAIL study: effect of e-Health individually tailored encouragements to physical exercise on aerobic fitness among adolescents with congenital heart disease--a randomized clinical trial

Intensive exercise may be an important part of rehabilitation in patients with congenital heart disease (CHD). However, performing regular physical exercise is challenging for many adolescent patients. Consequently, effective exercise encouragements may be needed. Little is known on the effect of e-Health encouragements on physical fitness, physical activity, and health-related quality of life in adolescents. This trial is a nationwide interactive e-Health rehabilitation study lasting 1 year, centered on interactive use of mobile phone and Internet technology. We hypothesize that e-Health encouragements and interactive monitoring of intensive exercise for 1 year can improve physical fitness, physical activity, and health-related quality of life. Two hundred sixteen adolescents (age, 13-16 years) with surgically corrected complex CHD but without significant hemodynamic residual defects and no restrictions to participate in physical activity are in the process of being enrolled by invitation after informed consent. Physical fitness is measured as the maximal oxygen uptake (Vo(2)) at baseline and after 12 months by an assessor blinded to the randomization group. After baseline testing, the patients are 1:1 randomized to an intervention group or a control group. Individually fully automated tailored e-Health encouragements--SMS, Internet, and mobile applications--aimed at increasing physical activity are delivered to the participants in the intervention group once a week. The Bandura's Social Cognitive Theory inspires the behavioral theoretical background. The e-Health intervention and the Godfrey cycle ergometer protocol have been feasibility tested and seem applicable to adolescents with CHD. The trial is expected to contribute with new knowledge regarding how physical activity in adolescents with CHD can be increased and, possibly, comorbidity be reduced.