Kumahara H, Tanaka H, Schutz Y
Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.
Int J Obes Relat Metab Disord. 2004 Sep;28(9):1105-10. doi: 10.1038/sj.ijo.0802712.
The movement of the upper limbs (eg fidgeting-like activities) is a meaningful component of nonexercise activity thermogenesis (NEAT). This study examined the relationship between upper limb movements and whole body trunk movements, by simultaneously measuring energy expenditure during the course of the day.
A cross-sectional study consisting of 88 subjects with a wide range in body mass index (17.3-32.5 kg/m(2)). The energy expenditure over a 24-h period was measured in a large respiratory chamber. The body movements were assessed by two uniaxial-accelerometers during daytime, one on the waist and the other on the dominant arm. The accelerometry scores from level 0 (=immobile) up to level 9 (=maximal intensity) were recorded. The activities of subjects were classified into eight categories: walking at two speeds on a horizontal treadmill (A & B), ambling (C), self-care tasks (D), desk work (E), meals (F), reading (G), watching TV (H).
There was a significant relationship between the accelerometry scores from the waist (ACwaist) and that from the wrist (ACwrist) over the daytime period (R(2)=0.64; P<0.001). The ACwrist was systematically higher than the ACwaist during sedentary activities, whereas it was the reverse for walking activities. ACwrist to ACwaist ratio of activities E-H were above 1.0 and for walking activities (A-C) were below 1.0. A multiple regression analysis for predicting daytime energy expenditure revealed that the explained variance improved by 2% only when the ACwrist was added as a second predictor in addition to the ACwaist. This indicates that the effect of the ACwrist for predicting energy expenditure was of limited importance in our conditions of measurement.
The acceleration of the upper limbs which includes fidgeting is more elevated than that of the whole body for sitting/lying down activities. However, their contribution to energy expenditure is lower than whole body trunk movements, thus indicating that the weight-bearing locomotion activities may be a key component of NEAT. However, its contribution may depend on the total duration of the upper limb movements during the course of the day.
上肢运动（如坐立不安样活动）是非运动活动产热（NEAT）的一个重要组成部分。本研究通过在一天中同时测量能量消耗，探讨上肢运动与全身躯干运动之间的关系。
一项横断面研究，纳入88名体重指数范围较广（17.3 - 32.5 kg/m²）的受试者。在一个大型呼吸室内测量24小时内的能量消耗。白天通过两个单轴加速度计评估身体运动，一个放在腰部，另一个放在优势手臂上。记录从0级（=静止）到9级（=最大强度）的加速度计得分。受试者的活动分为八类：在水平跑步机上以两种速度行走（A和B）、漫步（C）、自我护理任务（D）、伏案工作（E）、用餐（F）、阅读（G）、看电视（H）。
白天腰部加速度计得分（AC腰部）与手腕加速度计得分（AC手腕）之间存在显著关系（R² = 0.64；P < 0.001）。在久坐活动期间，AC手腕系统地高于AC腰部，而在行走活动中则相反。活动E - H的AC手腕与AC腰部之比高于1.0，而行走活动（A - C）则低于1.0。一项预测白天能量消耗的多元回归分析表明，仅在将AC手腕作为除AC腰部之外的第二个预测因子添加时，解释方差提高了2%。这表明在我们的测量条件下，AC手腕对预测能量消耗的作用有限。
包括坐立不安在内的上肢加速度在坐/卧活动中比全身加速度更高。然而，它们对能量消耗的贡献低于全身躯干运动，因此表明负重运动活动可能是NEAT的关键组成部分。然而，其贡献可能取决于一天中上肢运动的总持续时间。
