Relationship between the 24-Hour Activity Cycle and 24-Hour Blood Pressure (PDS administrative supplement to R01HL153642)

Project Summary The proposed Postdoctoral Research Supplement will provide career development and research activities that will enable Dr. Boudreaux to establish an independent program of research. Dr. Boudreaux is trained in exercise physiology and physical activity epidemiology with a long-term goal to build a highly productive,

independently funded laboratory which examines the role of the 24-hour activity cycle in the prevention and treatment of cardiovascular disease. With aspirations of becoming one of the preeminent investigators in the field of exercise science and physical activity epidemiology research, Dr. Boudreaux has identified specific

training areas in which more advanced training will allow him to accomplish this goal. As such, he has assembled a multidisciplinary team of mentors to provide training in: (1) physical activity and sleep research methodology, (2) cardiovascular disease prevention research (3) advanced study design and statistics, (4)

research dissemination and transition to independence, and (5) education in the responsible conduct of research. For his research project, Dr. Boudreaux will utilize the infrastructure of the parent grant, a phase I/II dose finding clinical rial designed to identify the minimally effective dose of sedentary breaks to offset the

cardiometabolic harms of prolonged sitting. Participants completed two 8-hour laboratory visits that entail either a control condition (sitting for 8 hours) or an active condition (sedentary breaks at randomized dose). Building off the parent grant, the primary aim of the study is to characterize the relationship between the composition of

the 24-hour activity cycle and 24-hour blood pressure in adults. To address this aim, additional assessments are proposed for participants enrolled in the parent grant study including (1) ambulatory blood pressure monitoring (2) multi-device accelerometry. The proposed study is designed as a pilot which will allow Dr.

Boudreaux to collect feasibility data for conducting his proposed methods and protocol. Data collected from this study will be used to inform screening, participation, and dropout rates and to test methods and procedures for Dr. Boudreaux’s future K grant application wherein a larger and more focused study will be

proposed to investigate the dynamic relationship of the 24-hour activity cycle with blood pressure. Dr. Boudreaux’s efforts in this Postdoctoral Research Supplement may help to fill a pressing need for identifying optimal time spent in each component of the 24-hour activity cycle to protect against the harmful

consequences of dysregulation of the circadian rhythm of blood pressure.