High levels of habitual physical activity in west African adolescent girlsand relationship to maturation, growth, and nutritional status: Results from a 3-year prospective study

This study examines energy expenditure and physical activity levels for a s ample of 40 adolescent girls of the Sereer ethnic group of rural Senegal. T he girls were 13.3 +/- 0.5 years at the start of the study (June 1997) and were followed annually for the next 2 years during puberty. Data collected during each round included: 1) pubertal status (as assessed by breast devel opment and occurrence of menarche); 2) selected anthropometric dimensions ( weight, stature, arm circumference. and six skinfolds); and 3) physical act ivity levels quantitatively assessed using CSA accelerometers. During round s 1 and 3, activity was also qualitatively reported by direct minute-by-min ute observations. A food consumption survey was performed once during the 3 (rd) round, using an individual food weighing method. Girls of this sample had high levels of energy expenditure with daily physical activity levels ( PALs) ranging from 1.70 to 1.85 multiples of basal metabolic rate. Energy i ntakes were, on average, sufficient to meet energy and protein requirements , although micronutrient deficiencies were likely to exist. Activity levels declined with age between the 1(st) and 3(rd) rounds. Stepwise regression analyses showed that stature was negatively correlated with both total dail y and day-time activity, whereas the body mass index was positively associa ted with this measure. Pubertal status and subcutaneous fatness were not si gnificant predictors of activity levels. The contribution of these adolesce nt girls to the everyday tasks of the household was considerable. They spen t more than 3 hours 30 minutes per day in domestic duties. (C) 2001 Wiley-L iss, Inc.