1Department of Health and Kinesiology, Texas A&M University, College Station, TX; 2The Genetic and Biological Determinants of Physical Activity Consortium (GenBioPAC); 3Department of Biological Psychology, VU University Amsterdam, Amsterdam, THE NETHERLANDS; 4Departments of Nutrition and Exercise Physiology and Biomedical Sciences, University of Missouri, Columbia, MO; 5Department of Nutritional Sciences, University of Texas at Austin, Austin, TX; 6Department of Immunology, Genetics and Pathology, and Science for Life Laboratory, Uppsala University, Uppsala, SWEDEN; 7Department of Public Health and Institute for Molecular Medicine FIMM, University of Helsinki, Helsinki, FINLAND; 8Department of Zoology, Ohio Wesleyan University, Delaware, OH; 9Department of Genetics, University of North Carolina, Chapel Hill, NC; 10Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana–Champaign, Urbana, IL; 11Department of Movement Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Katholieke Universiteit Leuven, Leuven, BELGIUM; 12Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA; and 13Human Genomics Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA