3.3. Community-based studies

3.3.1. Uganda

RUTISHAUSER and WHITEHEAD (1972) used a modified time-motion method to evaluate the physical activity of 20 black, undernourished children and 5 well-nourished children of European parents, 1.5 to 3 years old. The black children weighed less and were shorter than the Europeans. Their dietary energy intake was 67 ±14 kcal/kg/d, or 33% lower than current recommendations (FAO/WHO/UNU, 1985). Dietary intakes measured in two of the expatriate children averaged 109 kcal/kg/d.

During two consecutive 5-hour daytime periods, an observer recorded the activities performed by a child and classified them into six categories. Table 3 shows that the African children spent significantly more time sitting and standing, and less time walking and running than the European children.

Applying the energy cost of activities of older children and adults (PASSMORE and DURNIN, 1955; DURNIN and PASSMORE, 1967) to the time allocations shown in Table 3, Rutishauser and Whitehead estimated that the Ugandan children had a daily expenditure of 78 kcal/kg/d, while the European children spent 98 kcal/kg/d. Using the energy cost of activities measured in preschool children to avoid the errors of applying data from adults (TORUN 1983; TORUN et al., 1983), the daily energy expenditure of the Ugandan and European children can be calculated as 74 and 79 kcal/kg/d, respectively. This left the latter with more dietary energy available for growth and for physical activity during the unsupervised hours of the study.

Table 3. Estimated time allocation of native Ugandan and European children, 1.5-3 years old (mean + standard deviation)

	Time allocated (minutes)
Activity	African	European
In bed a	600 to 720	660 to 780
Lying down	81 ±87	70 ±56
Being carried	7 ±17	31 ±46
Sitting	300 ±64 **	190 ±43
Standing	265 ±93 *	143 ±54
Walking	108 ±46 **	234 ±54
Running	17 ±17 **	54 ±32

a Ranges estimated from mothers' information.

Means differ: * p < 0.05; ** p < 0.01.

Source: Calculated from RUTISHAUSER and WHITEHEAD, 1972.

3.3.2 Guatemala

TORUN and CHEW (unpublished) studied 69 boys and girls, 26 years old, who lived in a poor neighborhood in the outskirts of Guatemala city. The activities that they performed between 8 a.m. and 5 p.m. were recorded and timed on two separate weekdays using a modified time-motion technique (TORUN, 1984). The 56 activities recorded were classified in six categories of physical effort, from sedentary to very heavy (Table 4).

Table 4. Activities performed by preschool children in a marginal area of Guatemala, and classified according to effort. The energy costs of the grouped activities were estimated as multiples of basal metabolic rate

Sedentary	Light	Moderate	Moderately heavy	Heavy	Very heavy
1.2 x BMR	2.0 x BMR	2.25 x BMR	2.5 x BMR	3.0 x BMR	4.0 x BMR
Carried by someone	Bathe, wash	Climb up and down	Bounce on bed	Carry garbage or water pail	Run, hop and jump
Eat	Dress, undress	Hang clothes	Climb tree	Cut firewood	Run with a load
Hurl stones with sling	Hammer while sitting	Miscellaneous play	Dance, hoola-hoop	Housechores squatting	Run uphill
Lie and play	Lift light objects	Run and stop (with a ball)	Jump from a chair	Running ball-games	Walk fast uphill
Lie or sit quietly	Open doors or drawers	Slide	Ride scooter	Swing suspendend from arms
Nap	Push a hammock	Spin around	Ride tricycle or bicycle	Walk fast, level ground
Play guitar	Push or pull a cart	Stand and carry something	Somersaults
Sit and play	Push or pull a light toy	Sweep floor	Walk with a load
Sit and carry something	Squat or crawl	Walk slowly level ground	Walk slowly uphill
Sit on swing	Stand and play	Walk with stick and hoop	Wrestle
Sleep late	Throw a ball	Wash clothes
Stand quietly	Walk with pauses
Stand and sit

Source: TORUN and CHEW, unpublished observations.

Twenty-one children were considered mildly malnourished, based on weights-for-height between 81 and 90% of the NCHS/WHO median values, whereas 43 had between 91 and 110%, and 5 between 112 and 119% of the standard weights-for-height.

Compared with the well-nourished children, the malnourished spent 11.2% more time in sedentary activities, and 4.8, 1.7 and 2.5% less time in light, heavy and very heavy activities, respectively (Figure 4A). The longer time spent in light physical activities at the expense of those that demanded more energy became even clearer, when the activities were classified in only three categories of physical effort (Figure 4B).

Figure 4a. Proportions of observed time devoted by well-nourished and mildly malnourished preschool children to activities that require different amounts of effort. From TORUN and CHEW, unpublished. A: 6 categories.

Figure 4b. Proportions of observed time devoted by well-nourished and mildly malnourished preschool children to activities that require different amounts of effort. From TORUN and CHEW, unpublished. B: 3 categories.

Energy expenditure was estimated applying energy-cost factors of 1.2, 2, 2.25, 2.5, 3 and 4 times basal metabolic rate (X BMR) to the six categories of activities observed. Based on information provided by the mothers, sleeping time was added at 1.0 X BMR, and an energy expenditure of 1.52 or 1.43 X BMR was assumed for the balance of 25 hours. The children with weight-for-height > 90% of the NCHS median had an estimated expenditure of 81 kcal/kg/d, compared with 77 kcal/kg/d among the mildly malnourished.

Sixty of the 69 children were studied again, 2 and 4 months after the beginning of a nutritional education and supplementation program, on 2 separate weekdays each time (TORUN and CHEW, unpublished). At the end of the 4-month period, weight-for-height had increased by 3% or more in 23 children, remained stable within ±3% in 27, and decreased more than 3% in 10 children. An analysis was done of the time that those three groups of children dedicated before and after the intervention to activities that demanded different levels of physical effort.

Figure 5 shows that the children whose nutritional status improved, reduced the time dedicated to sedentary and light activities and significantly increased the time in moderate activities. On the other hand, the children whose nutritional status deteriorated, increased the time devoted to sedentary activities by reducing heavy activities.

Figure 5. Changes in proportions of time allocated by preschool children to activities of different physical effort as their nutritional status changes. From TORUN and CHEW, unpublished.

The comparison between groups (Figure 5), showed that the children whose weight-for-height improved: (a) reduced the time spent in sedentary and light activities, in contrast with the other two groups, (b) increased the performance of moderate physical activities, and (c) continued with the same proportion of heavy activities, in contrast with the children who lost weight-for-height.