In the first 10 days following recruitment, participants met with the research coordinator and were provided with an accelerometer (GT3X) and completed self-report baseline measures. Provided along with the RiseTx application is the Jawbone, which is a wrist-worn device that can assess activity patterns throughout the day and provide sensory alerts to stand after prolonged sitting (i.e., ≥30 minutes of sedentary time). The intervention consisted of five phases following initial data collection, including a baseline phase (weeks 1-2) where participants self-monitored their typical leisure time PA (i.e., step counts) and were asked to 'sync' their Jawbone with the RiseTx application to view their daily progress and steps. This daily self-monitoring process continued over the remaining intervention period. Based on a previously tested ramped step count approach that focuses on increasing walking by an extra 1000 daily steps over a set period, participants attempted to increase daily steps by 1000 over the average of their baseline week. Phases I-III involved progressive release of self-regulatory strategies (e.g., action planning) on the application and targeted changes in both sitting time (and breaks in sitting time) and step counts. Phase I (weeks 3-4) focused on increasing low intensity, incidental movement, through the use of an alerting device, and the Jawbone (reminder to break SED). At this time, an additional +1000 daily step increment was set above baseline. Phase II (weeks 5-6) targeted shorter planned PA (of up to 10 mins) by having participants form action plans on the application for both reducing SED and increasing PA. An additional +1000 daily step increment was set above Phase I. Phase III (weeks 7-8) focused on promoting longer, moderate intensity PA (>10 min), where participants used the application to form coping plans for barriers to reducing sitting time or engaging in PA. An additional +1000 daily step increment was set above Phase II step target. A 4-week consolidation phase (Phase IV and V; weeks 9-12) followed, where participants received weekly reminders that encouraged them to continue to use the RiseTx application to practice combining the different self-regulatory strategies learned in Phases I-III. Following the intervention, there was a 12-week maintenance period (weeks 13-24) where participants no longer received weekly self-regulatory practice reminders, yet still had access to the application.