Two American collegiate football linemen completed physical activity surveys, anthropometric assessments, dietary recalls, and blood draws across a 20-month period during which Player A continued training professionally in football while Player B transitioned out of the sport after his final collegiate season. Few changes were observed for Player A, whereas notable changes in physical activity, body mass, and endocrine factors associated with metabolic regulation were noted in Player B. Considerable alterations in physical activity and biomarkers occurred in the immediate transition out of competitive football, suggesting the possibility of long-term health consequences in the absence of future positive lifestyle behavioral changes. Alternatively, the adoption or maintenance of health behaviors could reverse risks. With a greater emphasis on lifespan wellness, this level 2 exploratory case series illustrates a key opportunity for athletic trainers to monitor athletes' cardiometabolic risks over an extended period and implement transitional care strategies to promote postcompetitive health. [ABSTRACT FROM AUTHOR]