Dietary intake and observed activity of stunted and non-stunted children in Kingston, Jamaica. Part II: Observed activity.
It is generally believed that activity levels are reduced in poorly nourished children. This may conserve energy, but may have a detrimental effect on mental development. However there are few data which support this hypothesis. No previous studies were found which looked at the activity levels of stunted children. In this study we modified the time and motion observation methods of Torun (1984) by using recording periods of 1 instead of 10 min. This significantly reduced the estimated time spent by young children in moderate and vigorous activities. Four hours of observing young children while they were awake, using the modified method, produced highly reliable data. The activity levels of a subsample of children described in part I were observed. The children were aged 12-24 months and were observed for 4 h on 2 d. Seventy-eight stunted children (height less than -2 SD of median, NCHS) were compared with 26 non-stunted children (height greater than -1 SD). The stunted children were significantly less active than the non-stunted children, although the difference in activity rating was small (3.4 per cent). They spent more time in light activities (P less than 0.001) and less time in moderate or vigorous activities (P less than 0.01). Both groups slept a similar amount. Using Torun's values for the energy cost of activities it appears unlikely that the reduced activity would conserve energy to a great extent, but it may still be of biological importance, since it is comparable to the energy cost of growth at this age. Activity levels increased with age but were not significantly related to weight for height.(ABSTRACT TRUNCATED AT 250 WORDS)
Gardner
J M
JM
Tropical Metabolism Research Unit, University of the West Indies, Kingston, Jamaica.
Grantham-McGregor
S M
SM
Chang
S M
SM
Powell
C A
CA
D002675:Child, Preschool; D004034:Diet Surveys; D004734:Energy Metabolism; D006801:Humans; D007223:Infant; D007563:Jamaica; D009748:Nutrition Disorders / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology*; D005082:Physical Exertion; D013996:Time and Motion Studies