Active transportation, e.g. walking or cycling to school or work, may contribute to energy balance, i.e. preventing unwanted weight gain, and prevent becoming overweight. Some studies have been conducted looking at the association between  active commuting to school and weight status among youth, but no clear conlusion can be drawn. Some recent studies suggest that cycling to school may make a bigger difference than walking to school. The purpose of our study, recently published in the Scandinavian Journal of Medicine and Science in Sport, (with Dr. Elling Bere as first author) was to assess the association between cycling to school and weight status in two cities, Rotterdam and Kristiansand, i.e. in the Netherlands and Norway, two countries where cycling to school remains common. Data from two studies, ENDORSE (Rotterdam) and Youth in Balance (Kristiansand), were used including, respectively, 1361 and 1197 adolescents around 14 years old. The adolescents were categorized as cyclist or non-cyclist based on questionnaires asking them about their usual mode of transportation to school. Twenty-five and 18% were categorized as overweight, and 35% and 31% were categorized as cyclists, in Rotterdam and Kristiansand, respectively. Further analyses showed that youth who cycled to school were about half as likely to be overweight than their peers who did not, after adjusting for a range of other possible 'reasons' for being overweight. These results thus suggest that cycling to school may 'protect' against overweight, but more rigorous research is necessary.