The increasingly sedentary habits of children, and rising obesity levels, are prompting concern for children's future health. Children with autistic spectrum condition (ASC) show a clear trend in this regard. Within school, an understanding of how an individual's fitness compares to age norms is important in order to design appropriate exercise programmes. This study, by Maurice Place, Kathleen Dickinson and Joanna Reynolds, all based at Northumbria University, assessed 100 children with ASC and learning difficulty, and found a wide variation in fitness levels as measured by the Eurofit tests. In addition the measure of cardio-pulmonary fitness (VO[superscript 2 max]) was generally poor. In boys, body mass index (BMI) showed only a modest correlation with this measure of cardio-pulmonary fitness, with the results for the girls not being significant. Using a variant of the established BMI calculation did not improve the correlation. To our knowledge this article offers the first set of published Eurofit test results for children with ASC and highlights the generally poor level of cardio-pulmonary fitness in this group of children.