ORIGINAL ARTICLE Cardiometabolic Risk in Adolescents: Associations with Physical Activity, Fitness, and Sleep Amanda J. Countryman, M.S. & Patrice G. Saab, Ph.D. & Maria M. Llabre, Ph.D. & Frank J. Penedo, Ph.D. & Judith R. McCalla, Ph.D. & Neil Schneiderman, Ph.D. Published online: 19 October 2012 # The Society of Behavioral Medicine 2012 Abstract Background Physical activity and fitness are independently associated with cardiometabolic dysfunction, and short sleep duration is an emerging marker of obesity. Few have examined interrelations among these factors in a compre- hensive risk model. Purpose Investigate the influence of behavioral and lifestyle risk factors on the metabolic syndrome and inflammation. Methods A sample of 367 15–17-year-olds (73 % boys) from ethnic minority groups (45.8 % Hispanic, 30.8 % Black), most with elevated blood pressure (72 %), under- went aerobic fitness testing, blood sampling, and completed behavioral questionnaires. Results Structural model results are consistent with the notion that short sleep duration, poor sleep quality and fatigue, and decreased physical activity are associated with increased risk of metabolic syndrome and inflammation possibly via effects on reduced cardiorespiratory fitness. Conclusions The combination of negative lifestyle and be- havioral factors of physical inactivity, sleep loss, and poor fitness has serious implications for cardiovascular health complications in at-risk youth. Keywords Cardiorespiratory fitness . Behavioral factors . Metabolic syndrome . Inflammation . Pediatrics Introduction Increased prevalence of obesity, elevated blood pressure (BP), insulin resistance, and inflammation in adolescents has stimulated investigation into how these factors contrib- ute to cardiovascular morbidity and mortality. Although the causes are multifactorial, sedentary behavior and low levels of physical activity contribute to the development of the metabolic syndrome and inflammatory states [1, 2]. Limited work has evaluated the relative contribution of sleep dura- tion as an intermediate risk factor of cardiovascular disease; however, emerging evidence points to parallel trends be- tween increased risk factor prevalence and decline in sleep duration as a potential explanation for how other lifestyle and behavioral factors may converge to influence cardiome- tabolic disease [3]. A 2006 U.S. National Sleep Foundation Survey found that 62 % of ninth to twelfth graders get an insufficient amount of sleep on school nights (<8 h). More than half of those adolescents report less sleep than they feel they need and are likely to report feeling too tired to engage in exercise and other physical activities [4], thus compound- ing the physiologic consequences of sleep loss. Given that risk factors often emerge during adolescence as a result of initiating health-compromising behaviors, and both behav- ioral patterns and their physiologic consequences are thought to extend later into life [5], it is important to exam- ine in youth the relative influence of multiple cardiometa- bolic risk factors, including sleep. In adults, persistent low levels of fitness are associated with increases in the metabolic syndrome and specific inflamma- tory markers such as IL-6, C-reactive protein (CRP), and fibrinogen [2, 6]. Despite evidence that fitness patterns from adolescence persist during adulthood [7], relationships be- tween aerobic fitness and metabolic syndrome and inflamma- tory outcomes are not well established in youth [1, 2]. It has been proposed that physical activity may, over time, improve A. J. Countryman (*) : P. G. Saab : M. M. Llabre : J. R. McCalla : N. Schneiderman Department of Psychology, University of Miami, P.O. Box 248185, Coral Gables, FL 33124-0751, USA e-mail: amanda.countryman@gmail.com F. J. Penedo Northwestern University, Chicago, IL, USA ann. behav. med. (2013) 45:121–131 DOI 10.1007/s12160-012-9428-8