The ABC of Physical Activity for Health: a consensus statement from the British Association of Sport and Exercise Sciences.
O'Donovan G, Blazevich AJ, Boreham C, Cooper AR, Crank H, Ekelund U, Fox KR, Gately P, Giles-Corti B, Gill JM, et al. J Sports Sci. 2010 Apr; 28(6):573-91.