Aerobic work capacity of mentally retarded boys and girls in junior high schools

Abstract

The maximal oxygen uptake (Vo2 max) and ergometer load at a heart rate of 170 beats/min (PWC170) were determined in mentally retarded children (74 boys and 53 girls) of ages 12-15, whose IQ ranged from 36 to 91, and the results were compared with those for normal children. Mentally retarded boys and girls showed significantly inferior body height and weight, but no significant difference was found in skinfold thickness. The mean value of PWC170 for boys and girls was 14.34 kpm/kg/min and 11.31 kpm/kg/min, respectively, significantly less than that of the normal group. The mentally retarded boys had mean VO2 max per unit body weight of 42.4 ml/kg/min, which was significantly less than the 51.2 ml/kg/min of normal boys. The mentally retarded girls had a mean of 33.1 ml/kg/min which was also less than the 41.3 ml/kg/min of normal girls. The correlation coefficient between body weight and PWC170 (kpm/min) was 0.711 and 0.720 for boys and girls, respectively, while that between body weight and VO2 max (liter/min) was 0.641 for boys and 0.656 for girls. No significant correlation was found between IQ and PWC170 (kpm/kg/min) nor between IQ and VO2 max (ml/kg/min) both for boys and for girls. Similarly, no significant correlation was found between mental age and the VO2 max value (ml/kg/min).