Counseling generally encourages exercise, according to Dr. Melvyn Hillsdon of University College London and colleagues. However, the researchers found no evidence that counseling can help people reach a specific exercise goal.
"More research is needed to establish which methods of exercise promotion work best in the long term to encourage different types of people to be more physically active," Hillsdon says, noting that most of the studies included in the review lasted less than a year.
The review appears in the January issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
Hillsdon and colleagues reviewed 17 studies that included 6,255 healthy adults age 16 and older. All of the studies were randomized controlled trials that compared different ways to encourage sedentary adults to become more physically active.
The studies measured the effects of interventions such as individual and group counseling, telephone calls, written motivational materials and supervised and unsupervised exercise.
Hillsdon and colleagues say continuing professional support combined with self-directed exercise may provide the most consistent results, but they acknowledge the studies vary too widely to recommend any single approach.
The differences between the studies also made it difficult to "determine if any type of physical activity is more likely to be adopted than any other type of physical activity," Hillsdon says.