There is a paucity of research on factors influencing long-term adherence to lifestyle modification. We conducted a mixed-method study to explore the psychological factors of dietary and physical activity (PA) adherence among Chinese adults with overweight and obesity at 10 months after enrollment of a community-based lifestyle modification program in Hong Kong. We recruited Chinese adults newly enrolled in a culturally adapted lifestyle modification program and followed them for 10 months. For the quantitative study, primary outcomes were dietary and PA adherence scores while secondary outcomes included knowledge, self-efficacy, motivation and stage of change. For the qualitative study, data were collected using semi-structured interviews and observation. A total of 140 participants completed the 10-month follow-up. They reported moderate level of dietary adherence but low level of PA adherence at 10 months. Multivariable regression analyses revealed that greater improvement in nutrition knowledge and diet stage of change predicted higher dietary adherence while greater improvement in PA self-efficacy and PA stage of change predicted higher PA adherence. Qualitative data on 26 participants suggest that participants' knowledge and self-efficacy but not motivation were enhanced during the program. The findings of this study enhanced our understanding on factors influencing long-term adherence to lifestyle changes.
Keywords: adherence; adults; diet; healthy lifestyle; mixed-method study; obesity management; physical activity; psychological factors.