Helge Hebestreit, MD, Professor of Pediatrics, is currently director of the CF centre in Würzburg, Germany and Vice Chair of Pediatrics. Prof. Hebestreit received his medical training in Würzburg between 1982 and 1989 and continued his education in Würzburg for specializations in pediatrics, sports medicine, and pediatric pulmonology. During a 2-year post doctoral fellowship with Prof. Dr. Oded Bar-Or from McMaster University in Hamilton/Ontario, Canada, Prof. Hebestreit participated in research involving children with chronic health conditions and physical exercise. This topic remained the focus of his scientific interest thereafter. Since 1998, Prof. Hebestreit studied together with his wife, a pediatrician running the CF clinic in Würzburg, the effects of physical exertion and physical training on patients with cystic fibrosis. Prof. Hebestreit is the coordinator of the Exercise Working Group of the European Cystic Fibrosis Society which developed several documents on exercise testing, physical activity assessment and exercise counselling / advice in cystic fibrosis. He is principal investigator of the international multi-centre study ACTIVATE-CF which assesses the effects of an exercise program in CF. He is also consultant to Vertex Pharmaceuticals in a phase IV study with physical fitness as primary outcome. Prof. Hebestreit has published more than 60 original papers on exercise physiology and conditioning in healthy people and those with various chronic health conditions as well as several review papers and book chapters.