RT Journal Article SR Electronic T1 Health benefits of physical activity JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 773 OP 776 DO 10.1503/cmaj.1060095 VO 175 IS 7 A1 Herbert H. Nehrlich YR 2006 UL http://www.cmaj.ca/content/175/7/773.3.abstract