The successful completion of the Oslo Marathon by a patient with cystic fibrosis.

Metabolic consequences of prolonged, severe exercise were investigated in a well trained 16-year-old boy with cystic fibrosis (CF) who completed the Oslo Marathon (42 195 m). His CF was diagnosed 6 years earlier. He had minimal radiological lung changes and a maximal oxygen uptake of 63.0 ml/kg/min. Several blood, urine and lung function parameters as well as body weight, fluid intake and rectal temperature were measured. None of the findings differed from those reported in healthy marathoners. Interestingly, no changes were found in the serum concentrations of electrolytes.