A study of the food intake and activity of a group of urban adolescents

Abstract

1. Information was obtained on the activity and food intake of ninety-two boys and 186 girls aged 16–19 years over a period of 7 days. Seventy-four boys and 132 girls were students, and eighteen boys and fifty-four girls were employed.2. Each subject recorded daily activity on a chart divided into squares corresponding to 5 min, using a code letter for each type of activity. The amounts of all foods and beverages consumed each day were recorded in a food diary.3. The energy expenditure of each subject was estimated from selected values for the energy cost of each activity. The intakes of calories and nutrients were calculated from tables of food composition.4. It was found that the subjects spent very little time in strenuous physical exertion. There were slight differences between the age-group and the occupation groups, but between 78 and 80% of the total time was spent in bed or seated, 14–20% in very light to light physical activity and only 1.5–4.4% in any activity greater than walking at an even pace.5. The group means for estimated energy expenditure in kcal, with their standard deviations, were: schoolboys aged 16–17, 2780 ± 250; employed boys aged 16–17, 2890±240; schoolboys aged 18–19, 2710±280; employed boys aged 18–19, 2749±270; schoolgirls aged 16–17, 2030±170; employed girls aged 16–17, 2140±240; schoolgirls aged 18–19, 2040±190; trainee teachers aged 18–19, 1900±140; employed girls aged 18–19, 2070±160.6. Group means for the intake of kcal were: schoolboys aged 16–17, 3040±540; employed boys aged 16–17, 2730±520; schoolboys aged 18–19, 3110±450; employed boys aged 18–19, 2700–170; schoolgirls aged 16–17, 2140±420; employed girls aged 16–17, 1910±310; schoolgirls aged 18–19, 2400 ± 310; trainee teachers aged 18–19, 2020 ± 330; employed girls aged 18–19, 2030±4407. The employed girls aged 16–17 had lower intakes of calories and all nutrients than the schoolgirls of the same age.8. No correlation was found between the weight and calorie intake of individual subjects, nor between their calorie intake and energy expenditure during the time interval studied. The results indicated that for these Australian subjects, calorie balance was not achieved over a period of a few days. This is in accord with evidence of workers in other countries.9. The findings suggest the need for further studies on the nutritional status of Australian employed girls aged 16–17.