title: Effects of exercise intensity and nutrition advice on myocardial function in obese children and adolescents: a multicentre randomised controlled trial study protocol.
abstract: BACKGROUND
  The prevalence of paediatric obesity is increasing, and with it, lifestyle-related diseases in children and adolescents. High-intensity interval training (HIIT) has recently been explored as an alternate to traditional moderate-intensity continuous training (MICT) in adults with chronic disease and has been shown to induce a rapid reversal of subclinical disease markers in obese children and adolescents. The primary aim of this study is to compare the effects of HIIT with MICT on myocardial function in obese children and adolescents.
  
  
  METHODS
  Multicentre randomised controlled trial of 100 obese children and adolescents in the cities of Trondheim (Norway) and Brisbane (Australia). The trial will examine the efficacy of HIIT to improve cardiometabolic outcomes in obese children and adolescents. Participants will be randomised to (1) HIIT and nutrition advice, (2) MICT and nutrition advice or (3) nutrition advice. Participants will partake in supervised exercise training and/or nutrition sessions for 3 months. Measurements for study end points will occur at baseline, 3 months (postintervention) and 12 months (follow-up). The primary end point is myocardial function (peak systolic tissue velocity). Secondary end points include vascular function (flow-mediated dilation assessment), quantity of visceral and subcutaneous adipose tissue, myocardial structure and function, body composition, cardiorespiratory fitness, autonomic function, blood biochemistry, physical activity and nutrition. Lean, healthy children and adolescents will complete measurements for all study end points at one time point for comparative cross-sectional analyses.
  
  
  BACKGROUND
  This randomised controlled trial will generate substantial information regarding the effects of exercise intensity on paediatric obesity, specifically the cardiometabolic health of this at-risk population. It is expected that communication of results will allow for the development of more effective evidence-based exercise prescription guidelines in this population while investigating the benefits of HIIT on subclinical markers of disease.
  
  
  BACKGROUND
  NCT01991106.
authors.affiliation: School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Brisbane, Queensland, Australia.
authors.forename: Katrin A
authors.initials: KA
authors.lastname: Dias
authors.affiliation: School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Brisbane, Queensland, Australia.
authors.forename: Jeff S
authors.initials: JS
authors.lastname: Coombes
authors.affiliation: School of Sport Science, Exercise and Health, The University of Western Australia, Perth, Western Australia, Australia Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Green
authors.affiliation: School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Brisbane, Queensland, Australia.
authors.forename: Sjaan R
authors.initials: SR
authors.lastname: Gomersall
authors.affiliation: School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Brisbane, Queensland, Australia.
authors.forename: Shelley E
authors.initials: SE
authors.lastname: Keating
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Arnt Erik
authors.initials: AE
authors.lastname: Tjonna
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Siri Marte
authors.initials: SM
authors.lastname: Hollekim-Strand
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Mansoureh Sadat
authors.initials: MS
authors.lastname: Hosseini
authors.affiliation: Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway Department of Pediatrics, St. Olav's University Hospital, Trondheim, Norway.
authors.forename: Torstein Baade
authors.initials: TB
authors.lastname: Ro
authors.affiliation: Department of Radiology, Trondheim University Hospital, Trondheim, Norway.
authors.forename: Margrete
authors.initials: M
authors.lastname: Haram
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Else Marie
authors.initials: EM
authors.lastname: Huuse
authors.affiliation: Children's Nutrition Research Centre, The University of Queensland, Brisbane, Queensland, Australia Queensland Children's Medical Research Institute, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Peter S W
authors.initials: PS
authors.lastname: Davies
authors.affiliation: Heart Care Partners, The Wesley Hospital, Brisbane, Queensland, Australia.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Cain
authors.affiliation: Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia Department of Paediatric Endocrinology, Lady Cilento Children's Hospital, Brisbane, Queensland, Australia.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Leong
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Charlotte B
authors.initials: CB
authors.lastname: Ingul
mesh_terms: D000293:Adolescent; D001315:Australia; D001783:Blood Flow Velocity; D002648:Child; D002985:Clinical Protocols; D004032:Diet; D015444:Exercise / Q000502:physiology*; D005260:Female; D006293:Health Promotion; D006321:Heart / Q000503:physiopathology*; D000072696:High-Intensity Interval Training; D006801:Humans; D008019:Life Style; D008297:Male; D009206:Myocardium; D009664:Norway; D063766:Pediatric Obesity / Q000503:physiopathology*; D005082:Physical Exertion / Q000502:physiology*; D012107:Research Design
keywords: High intensity interval training; Myocardial function; NUTRITION & DIETETICS; Paediatric obesity; Vascular function; Visceral adipose tissue