My Heart Counts Cardiovascular Health Study: Next Gen

The My Heart Counts Cardiovascular Health Study will utilize mobile health capabilities of smartphones to assess daily activity measures and compare these to measures of cardiovascular health risk factors and fitness. The study aims to collect cardiovascular health data on a diverse population by making the application available on both iOS and Android platforms. Using smartphone sensors and connected devices, the study will collect physical activity metrics, heart rate data, and responses to health questionnaires. The study includes a randomized crossover trial component examining the effectiveness of personalized activity coaching prompts generated by a language model compared to generic prompts.

NCT Number	NCT07428122
Lead Sponsor	Stanford University Collaborators: Imperial College London, University of Washington
Conditions	Cardiovascular Health, Physical Activity
Enrollment	15,000 participants
Start Date	2026-04-30
Primary Completion	2035-12-31 (estimated)
Study Completion	2035-12-31 (estimated)
Updated on ClinicalTrials.gov	2026-02-23