Physical activity patterns of rural Senegalese adolescent girls during the dry and rainy seasons measured by movement registration and direct observation methods

Objective: To study the physical activity patterns and daily estimates of energy expenditure (EE) of rural adolescent Senegalese girls. Design: Physical activity was monitored using a portable accelerometer during four consecutive days and within the same time, by direct observation during two consecutive days. Adolescent girls were followed during the dry season (June, n = 40) and again during the rainy season (September, n = 30) Setting: The Niakhar district in the central part of Senegal. Subjects: Forty adolescents (13.3 +/- 0.5 y) drawn from a sample of 221 rural girls followed as part of a longitudinal study on growth and nutrition during puberty. Results: Reliability of movement counts was acceptable (intraclass correlation, R = 0.71). There was a linear relationship between movement counts and observed scores. Predicted physical activity levels were high: 1.90 +/- 0.12 Mets (EE: 9.03 +/- 0.77 MJ). Physical activity levels derived from movement counts during the day are higher in the rainy season than during the dry season. This coincided with a depression in nutritional indicators during the rainy season apparent in the overall sample. Sleep duration appeared to be short in both seasons (6-6.5 h per night). Senegalese adolescents participated in daily household tasks but time spent in productive activities, agricultural or handicraft, was less than 1 h per day. Conclusions: Estimates of activity-related EE of Senegalese adolescents were greater than those of adolescents from developed countries but closed to recent. estimates for rural areas in developing countries. Energy requirements drawn from developed countries do not necessarily apply to African adolescent girls.