"Prior to this study, we did not have empirical data to support the claim that diet and exercise actually worked to prevent knee pain," said lead researcher Daniel White, assistant professor of physical therapy at the University of Delaware.
The study compared participants receiving intensive lifestyle intervention (ILI) to a comparison group receiving standard diabetes mellitus support and education (DSE), measuring knee pain at the end of one year and four years.
The trial that started in 2011 involved obese and diabetic adults aged 45 to 76.
"The analysis involved a subcohort of 2,889 subjects who reported no knee pain at baseline, but were at high risk due to obesity," White said.
The primary method of achieving weight loss was caloric intake restrictions, based on guidelines from the American Diabetes Association.
The diet limits total calories from fat to 30 percent while mandating at least 10 percent of calories to be obtained from protein.
Intervention for exercise relied heavily on unsupervised exercise at home, with a gradual progression to 175 minutes per week of moderate to vigorous physical exercise.
For most participants, the study notes, this activity consisted of brisk walking, with moderate-intensity walking encouraged as a primary type of physical activity.
"Among those we studied who were randomized to the diet and exercise intervention, it was found that they were 15 percent less likely to develop knee pain compared with their counterparts randomized to the control condition," said White.
The findings appeared in the journal Arthritis Care and Research.