Physical Activity and Physical Fitness

The focus of the PhenX (Phenotypes and eXposures) Toolkit is to provide researchers whose expertise lies outside a particular area with keymeasures identifıed by experts for uniform use in large-scale genetic studies and other extensive epidemiologic efforts going forward. The current paper specifıcally addresses the PhenX Toolkit research domain of physical activity and physical fıtness (PA/PF), which are often associated with health outcomes. A Working Group (WG) of content experts completed a 6-month consensus process in which they identifıed a set of 14 high-priority, low-burden, and scientifıcally supported measures. During this process, the WG considered self-reported and objectivemeasures that included the latest technology (e.g., accelerometers, pedometers, and heart-rate monitors). They also sought the input of measurement experts and other members of the research community during their deliberations. A majority of the measures include protocols for children (or adolescents), adults, and older adults or are applicable to all ages. Measures from the PA/PF domain and 20 other domains are publicly available and found at the PhenX Toolkit website, www.phenxtoolkit.org. The use of common measures and protocols across large studies enhances the capacity to combine or compare data across studies, benefıting bothPA/PF experts and non-experts. Use of these commonmeasures by the research community should increase statistical power and enhance the ability to answer scientifıc questions that previously might have gone unanswered. (Am J Prev Med 2012;42(5):486–492) © 2012 American Journal of Preventive Medicine