“We see an obvious increase in the number of fat bike accidents,” says ER doctor Loes Walraven of the Diakonessenhuis. “It mainly concerns young people between the ages of 12 and 16. A much larger number also have abdominal injuries. This means that the injuries are much more serious than in an accident with a normal bicycle.” Almost half of the victims are between 12 and 15 years old, according to SafetyNL figures.