1.Fifteen female farmers (aged 18–47 years) from two villages of the Mossi Plateau in Upper-Volta participated in a survey in which their daily activity pattern and their energy expenditure were assessed. Eight of the subjects were investigated twice, in March (dry season) when there is no agricultural activity, and in July–August (rainy season) when heavy physical work is performed: mostly hoeing, weeding and replanting sorghum (Sorghum vulgare) and millet (Pennisetum typhoïdes).
2. The mean height was 1.57 m and the mean weight 50.6 kg. The average percentage of body fat, calculated from skinfold thickness, was comparable to that of European females but the triceps skinfold was more than 60% below the standard value (Jelliffe, 1969). The type of activities and the period of time spent on each activity changed significantly with the season. The mean energy output rose from 9.7 MJ (2320 kcal) in March to 12.1 MJ (2890 kcal) in July–August for a 55 kg standard weight.
3. In this paper, the extent of both the dally activity pattern of women living in a subsistence agriculture and their energy output is estimated. The results suggest that during the rainy season, the energy requirements of female farmers are much higher than usually estimated.