Blackburn M W, Calloway D H
J Am Diet Assoc. 1976 Jul;69(1):24-8.
Resting and working metabolic rates and physical fitness of twenty-one mature women were studied at various intervals during the last half of pregnance and in sixteen of them again eight to twelve weeks postpartum. Basal rate (BMR) was increased more than body weight during pregnancy, and there was a small drop in BMR per unit body mass near term. Data on lean body mass (40K) suggest that the small terminal fall in BMR is not explained by a shift in body composition toward increased fat or water. The increase in energy cost of work paralleled the gain in body weight during preganacy. Net energetic efficiency thus appeared to be higher for work performed during pregnancy, if recovery rates are assumed to be uniform. However, according to their heart rate reponses to fixed hard work, the women were less fit during pregnancy than they were postpartum, with the level of fitness decreasing as pregnancy advanced. The prolonged rate of recovery suggests that oxygen uptake may be increased for a longer period after work in the pregnant woman. If this is true, energy expenditure will be seriously underestimated by the application of energy cost figures obtained in the conventional manner.
对21名成年女性在妊娠后半期的不同时间段进行了静息代谢率、工作代谢率和身体素质的研究，其中16名女性在产后8至12周再次接受研究。孕期基础代谢率（BMR）的增加超过了体重的增加，且接近足月时单位体重的BMR略有下降。关于瘦体重（40K）的数据表明，BMR在末期的小幅下降并非由身体成分向脂肪或水分增加的转变所解释。孕期工作的能量消耗增加与体重增加平行。因此，如果假设恢复率一致，那么孕期工作的净能量效率似乎更高。然而，根据她们对固定强度工作的心率反应，这些女性在孕期的身体素质不如产后，且随着孕期进展，身体素质水平下降。恢复时间延长表明，孕妇工作后氧气摄取可能会在更长时间内增加。如果情况属实，那么采用传统方式获得的能量消耗数据将会严重低估能量消耗。
