Abstract 047: Trajectories of Maintaining Recommended Amounts of Physical Activity in Young Adulthood and Associations with Abdominal Adiposity in Middle Age: The Cardia Study

Abstract

Background: Greater abdominal adiposity is associated with insulin resistance and obesity-related vascular disease. Physical activity (PA) is inversely associated with abdominal adiposity yet associations between trends in adherence to PA recommendations through young adulthood and abdominal adiposity in middle age is unclear. Objective: To identify common trajectories of maintaining recommended levels of PA through young adulthood and to examine associations between trajectories and abdominal adiposity at middle age. Methods: The Coronary Artery Risk Development in Young Adults (CARDIA) study is a population-based, prospective, observational study of black and white men and women. PA was assessed at 8 exams across 25 years of follow-up. PA trajectories were identified by group-based modeling (PROC TRAJ) based on likelihood of maintaining recommended PA levels across exams. Visceral, subcutaneous, and abdominal intermuscular adipose tissue volumes (cm3) were assessed by computed tomography at the year 25 exam (43-55 yrs, n=3180). Results: Four major PA trajectories were identified: highly active (27.3%), declining activity (18.2%), modestly active (20.7%) and always sedentary (33.8%). Abdominal adipose tissue volumes by PA trajectory, race, and sex are displayed in Figure 1. Among white men and women, abdominal adiposity was lowest in always active adults and highest in those always sedentary; higher abdominal adiposity was observed with declining activity compared to modest activity. In black women, highest levels of abdominal adiposity were observed with declining activity. Black men exhibited no differences in abdominal adiposity across PA trajectory groups. Conclusions: Maintaining recommended physical activity levels through young adulthood is associated with lower abdominal adiposity at middle age. Highly active adults who exhibit declining physical activity towards middle age exhibit higher abdominal adiposity compared to adults with consistent modest activity throughout adulthood.