John R. Sirard

John Sirard
Assistant Professor
159D Totman Building

Physical Activity and Health Lab


B.S., University of Massachusetts Amherst, 1991; M.S., University of Massachusetts Amherst, 1997; Ph.D., University of South Carolina, 2003; Postdoctoral Fellowship, Stanford University School of Medicine

Area(s) of Specialization: 

Measurement of Physical Activity; Social and Environmental Influences on Youth Physical Activity; School-Based Physical Activity Interventions

Research Description: 

The long-term goals of my research program are to develop, test, and disseminate successful intervention programs that work at multiple levels of influence to increase youth physical activity and decrease screen media use, leading to long-term improvements in physical, social, and mental health. 

To accomplish these long-term goals my research embraces the Social Ecological Model as a framework to better understand the multiple levels of influence on youth physical activity and sedentary behavior.  One facet of my research program is to better understand the social and physical environmental influences on youth physical activity and sedentary behavior.  The broad research questions here include, but are not limited to; How do friends influence adolescent physical activity and screen media use over time?  Do parental influences weaken as children enter and progress through adolescence?  How does an adolescent’s position within their social network affect their behavior?  How does the home environment (e.g., sport and play equipment, screen media equipment) and the neighborhood environment (e.g., crime, traffic, infrastructure) affect youth physical activity and sedentary behavior?

At the heart of the Social-Ecological Model are the individual-level behaviors and their health outcomes.  Therefore, another integral facet of my research program is to better understand how to quantify physical activity and sedentary behavior in youth.  We use accelerometers (i.e., motion sensors) to objectively quantify frequency, intensity, and timing of physical activity and inactivity but also rely on questionnaire data, when appropriate, to assess relevant contextual information (e.g., Where?  Who with?  Why?).

Key Publications: 

Sirard JR, Hannan P, Larson N, Graham DJ, Neumark-Sztainer D. Evaluation of 2 self-report measures of physical activity with accelerometry in young adults. J Phys Act Health. 10(1), 85-96, 2013.

Sirard JR, Bruening M, Wall M, Kim S, Eisenberg M, Neumark-Sztainer. Physical activity and screen time in adolescents and their friends. Am J Prev Med. 44(1), 48-56, 2013.

Hearst MO, Sirard JR , Lytle LA, Dengel D, Berrigan D. Comparison of three measures of physical activity and associations with blood pressure, HDL and body composition in a sample of adolescents. J Phys Act Health. 9(1), 78-85, 2012.

Martinson BC, Hearst MO, Vasquez-Benitez GX, Patnode CD, Sherwood NE, Parker ED, Sirard JR, Pasch K, Lytle LA. Obesogenic Family Types Identified Through Latent Profile Analysis. Ann Behav Med. 42(2), 210-220, 2011.

Sirard JR, Patnode CD, Hearst MO, Laska MN. Dog ownership and adolescent physical activity. Am J Prev Med. 40(3), 334-7, 2011.