Evidence of exercise-induced arterial hypoxemia in prepubescent trained children.
Exercise-induced arterial hypoxemia (EIAH) is a recognized phenomenon in highly trained adults. Like adult athletes, prepubescent trained children may develop high-level metabolic demand but with a limited lung capacity in comparison with adults. The purpose of this investigation was to search for evidence of EIAH in prepubescent trained children. Twenty-four prepubescent (age: 10.3 +/- 0.2 y) trained children (10.0 +/- 0.7 h of weekly physical activity) performed pulmonary function tests and a graded maximal exercise test on a cycle ergometer. EIAH was defined as a drop of at least 4% from resting level arterial oxygen saturation (Sao(2)) measured by pulse oximetry. EIAH was observed in seven children. Forced vital capacity (FVC), ventilatory response to exercise (Delta(E)/Deltaco(2)), and breathing reserve at maximal exercise were significantly lower, whereas tidal volume relative to FVC was higher in hypoxemic children than in nonhypoxemic children; weekly physical activity and maximal oxygen uptake were similar. Moreover, positive relationships were found between Sao(2) at maximal exercise and breathing reserve (r = 0.56; p < 0.05) or volume relative to FVC (r = 0.70; p < 0.01). EIAH may occur in prepubescent trained children with a relatively low maximal oxygen uptake (42 mL. min(-1). kg(-1)); however, the mechanisms remain unclear and need to be investigated more accurately.
Nourry
Cédric
C
UFR STAPS Liévin, Laboratoire d'Analyse Multidisciplinaire des Pratiques et Sportives, Chemin du Marquage, 62800 Liévin, France.
Fabre
Claudine
C
Bart
Frédéric
F
Grosbois
Jean-Marie
JM
Berthoin
Serge
S
Mucci
Patrick
P
D000328:Adult; D002648:Child; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006801:Humans; D000860:Hypoxia; D008297:Male; D010100:Oxygen / Q000097:blood*; D010806:Physical Education and Training; D011627:Puberty; D012129:Respiratory Function Tests; D013223:Statistics as Topic
D010100:Oxygen