Physical activity, melatonin concentrations, and circadian rhythm of oral body temperature in children with low waking basal body temperature

本研究的目的是调查低清醒基础体温儿童的日常体力活动、褪黑素浓度和体温昼夜节律。受试者(9-10岁)接受了为期一周的口腔体温(OBT)和日常体力活动的评估。在睡前也测量了褪黑激素。低温组(LOW)定义为&GT；1)早晚活动得分与日常体温呈正相关，即高体力活动组为晨间型；2)低体力活动组睡眠时间氧饱和度下降不足；3)日常体力活动与睡前褪黑素浓度呈显著正相关；4)日常体力活动与Δ呈显著正相关；5)低清醒基础体温儿童与正常清醒体温儿童相比，最低体温延迟时间明显延长。冬季睡眠时间和就寝时间分别显著低于夏季。然而，夏冬两季醒着的OBT组没有明显差异，观察到体力活动的增加。我们的结果提示，较低的体力活动水平可能影响OBT的昼夜节律。我们的数据还表明，低清醒的OBT可能与延迟的OBT昼夜节律有关。

The purpose of this study was to investigate the daily physical activity, the melatonin concentrations, and circadian rhythm of body temperature in children with low waking basal body temperature. The subjects (nine-ten yrs) were evaluated for oral body temperature (OBT) and daily physical activity over an one week period. Melatonin was also measured at bed time. Low temperature group (LOW) was defined as > 1 SD below the mean waking OBT.1) Morning-Evening score was correlated with the daily physical activity, that is high physical activity group is morning type.2) An insufficient decline in bedtime OBT was observed in low physical activity group.3) There was a significant positive correlation between the daily physical activity and the melatonin concentration of bedtime.4) There was a significant positive correlation between the daily physical activity and ΔOBT (waking OBT-BT in bedtime).5) The delayed time of minimum body temperature in children with low waking basal body temperature were compared with the children of the normal waking body temperature was observed.6) The OBT of waking, noon, and bedtime in winter were significantly lower than these in summer, respectively. However, there was no significant difference between summer and winter of the waking OBT in the group was observed the increase in physical activity.Our results suggest that the lower level of physical activity may affect OBT circadian rhythm. Our data also suggest that low waking OBT may be associated with delayed OBT circadian rhythm.