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Haskell WL, Lee IM, Pate RR, Powell KE, Blair SN, Franklin BA, Macera CA, Heath GW, Thompson PD, Bauman A; American College of Sports Medicine; American Heart Association.Haskell WL, et al. Among authors: macera ca.Circulation. 2007 Aug 28;116(9):1081-93. doi: 10.1161/CIRCULATIONAHA.107.185649. Epub 2007 Aug 1.Circulation. 2007.PMID: 17671237