1. Department of Paediatrics (K.B., K.K.O., D.B.D.), University of Cambridge, Addenbrooke’s Hospital, Cambridge CB2 0QQ, United Kingdom
2. Medical Research Council Epidemiology Unit (K.K.O., J.H.Z.), Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
3. Department of Paediatrics (N.M.), Rotunda Hospital, Dublin 1, Ireland
4. Department of Paediatrics (M.L.A.), University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom
5. Research Center for Exercise and Health (M.W.P.), Department of Biomedical Kinesiology, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium