Ndiaye Gnagna Mbaye, Benefice Eric
Epidemiology, Dakar, Senegal.
Ann Hum Biol. 2007 Jul-Aug;34(4):454-69. doi: 10.1080/03014460701383774.
In rural Africa, women and adolescent girls sustain a high burden of domestic and agricultural tasks. This could result in energy imbalance and impair their nutritional status.
The aim of the study was to investigate activity during the day and time spent in bed during the night for adult women and adolescent and preadolescent girls living in the same household. The hypothesis was that more prolonged physical inactivity and time spent in bed could be an efficient means for lowering energy expenditure and hence maintaining an adequate nutritional state.
Physical activity during the day was qualitatively recorded using 'spot observation' (Super 1989), and quantitatively using accelerometers. A total of 110 females--55 adult women, 45 adolescents and 10 preadolescents--were included in the study. Anthropometric measurements (weight, height and four subcutaneous skinfolds) served as indicators of nutritional status.
Day-to-day reliability of accelerometry counts was acceptable (average intraclass correlation coefficient = 0.73). Differences in daytime activity varied according to age group. Adolescent and preadolescent girls had higher overall activities than adults (p < 0.01). Preadolescent girls went to bed earlier and for longer periods than adult women (p < 0.001). There existed significant relationships between time spent in bed and activity during the day in adult women but not in adolescent or preadolescent girls. A significant relationship between nutritional status and physical activity indices was observed in preadolescent and adolescent girls, but not in women.
The findings partially support the hypothesis of some compensation of daytime activity by time spent in bed in adult women, but not in adolescent or preadolescent girls.
在非洲农村，成年女性以及青春期和青春期前女孩承担着繁重的家务和农业劳动任务。这可能导致能量失衡并损害她们的营养状况。
本研究旨在调查居住在同一家庭中的成年女性、青春期女孩和青春期前女孩白天的活动情况以及夜间卧床时间。假设是更长时间的身体不活动和卧床时间可能是降低能量消耗从而维持充足营养状态的有效方式。
白天的身体活动通过“定点观察”（Super，1989）进行定性记录，并使用加速度计进行定量记录。共有110名女性——55名成年女性、45名青少年和10名青春期前女孩——纳入本研究。人体测量指标（体重、身高和四处皮下褶厚度）作为营养状况的指标。
加速度计计数的日常可靠性是可接受的（平均组内相关系数 = 0.73）。白天活动的差异因年龄组而异。青少年和青春期前女孩的总体活动量高于成年人（p < 0.01）。青春期前女孩比成年女性上床睡觉更早且睡眠时间更长（p < 0.001）。成年女性的卧床时间与白天活动之间存在显著关系，而青少年和青春期前女孩则不存在。在青春期前和青春期女孩中观察到营养状况与身体活动指标之间存在显著关系，但成年女性中未观察到。
研究结果部分支持成年女性通过卧床时间对白天活动进行某种补偿的假设，但青少年和青春期前女孩不支持。
