Epidemiology of Cerebral Palsy

infrared measuring principle and the O2 analyser upon the paramagnetic principle, while the spirometer function on a bellows and slide-valve principle. The ergometer (Jager, Germany) was electrically braked. The tests were symptom-limited and interrupted due to general exhaustion (1). The ordinary objective criteria to determine maximum exercise (W,,,) were followed; the respiratory quotient (RQ) greater than 1.0, the blood lactate values above 7.0 mmoVl and an increase in ventilation without further increase in oxygen uptake (2). Two of the C F boys did not reach these criteria. These boys were highly restricted by their lung function as indicated by maximum heart rates of 141 and 149, respectively, and their maximal exercise periods lasted only 2 minutes. During testing of maximal aerobic power it is important to find a maximum work load that the tested subjects can sustain for at least 2 '/2-3 minutes. If a max test lasts only 2 minutes the RQ usually will be relatively low in spite of supramaximal loading, due to a time lag of C02 elimination compared with 0 2 uptake in expiratory air. Further we would like to encourage our colleagues during exercise testing also to look critically at high RQ values during max testing, because we have found a general trend towards higher RQ values during maximal exercise when using automated systems, than when using the Douglas bag micro Schollander method. In our study we found a close correlation between Volmax and Schwachman scores, but