The Multidimensional Individualized Physical ACTivity (MIPACT) trial was a parallel-group, randomized clinical trial that recruited patients at risk of cardiovascular disease and/or type II diabetes between May 2014 and June 2015 from five primary care practices in the UK. Data collection was completed in November 2016. Intervention group participants (n=120) received personal multidimensional PA feedback using a sophisticated wearable monitor and customized web-app for 3 months, and were offered five health trainer-led sessions. All participants received standardized information regarding PA. Control group participants (n=84) received no further intervention. Among the 204 participants randomized (mean [SD] age, 64 [10] years; 46% women) 186 (90%) completed the study. The dataset includes demographic information and objectively-assessed PA dimensions and health-related outcomes at 3 and 12 months.