Promises and pitfalls of emerging measures of physical activity and the environment.
Troiano
Richard P
RP
National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA. troianor@mail.nih.gov
Freedson
Patty S
PS
D003625:Data Collection / Q000379:methods*; D004779:Environment Design; D006801:Humans; D009043:Motor Activity; D012106:Research / Q000592:standards; D012107:Research Design; D013997:Time Factors; D016138:Walking