[1] Univ Alberta, Dept Pediat, Edmonton, AB T6G 1C9, Canada
[2] Leeds Beckett Univ, Inst Sport Phys Act & Leisure, Carnegie Fac, Ctr Act Lifestyles, Headingley Campus, Leeds LS6 3QS, W Yorkshire, England
[3] Harvard Univ, Harvard Med Sch, Boston, MA 02115 USA
[4] Wake Forest Sch Med, Dept Pediat, Winston Salem, NC 27157 USA
[5] Brenner Childrens Hosp, Brenner FIT Families Training, Winston Salem, NC 27157 USA