MRC Epidemiology Unit, School of Clinical Medicine, University of Cambridge, Cambridge, UK.
MRC Elsie Widdowson Laboratory, 20 Fulbourn Road, Cambridge, UK.
Int J Obes (Lond). 2019 Nov;43(11):2333-2342. doi: 10.1038/s41366-019-0352-x. Epub 2019 Apr 2.
Many large studies have implemented wrist or thigh accelerometry to capture physical activity, but the accuracy of these measurements to infer activity energy expenditure (AEE) and consequently total energy expenditure (TEE) has not been demonstrated. The purpose of this study was to assess the validity of acceleration intensity at wrist and thigh sites as estimates of AEE and TEE under free-living conditions using a gold-standard criterion.
Measurements for 193 UK adults (105 men, 88 women, aged 40-66 years, BMI 20.4-36.6 kg m) were collected with triaxial accelerometers worn on the dominant wrist, non-dominant wrist and thigh in free-living conditions for 9-14 days. In a subsample (50 men, 50 women) TEE was simultaneously assessed with doubly labelled water (DLW). AEE was estimated from non-dominant wrist using an established estimation model, and novel models were derived for dominant wrist and thigh in the non-DLW subsample. Agreement with both AEE and TEE from DLW was evaluated by mean bias, root mean squared error (RMSE), and Pearson correlation.
Mean TEE and AEE derived from DLW were 11.6 (2.3) MJ day and 49.8 (16.3) kJ day kg. Dominant and non-dominant wrist acceleration were highly correlated in free-living (r = 0.93), but less so with thigh (r = 0.73 and 0.66, respectively). Estimates of AEE were 48.6 (11.8) kJ day kg from dominant wrist, 48.6 (12.3) from non-dominant wrist, and 46.0 (10.1) from thigh; these agreed strongly with AEE (RMSE 12.2 kJ day kg, r ~ 0.71) with small mean biases at the population level (6%). Only the thigh estimate was statistically significantly different from the criterion. When combining these AEE estimates with estimated REE, agreement was stronger with the criterion (RMSE ~1.0 MJ day, r ~ 0.90).
In UK adults, acceleration measured at either wrist or thigh can be used to estimate population levels of AEE and TEE in free-living conditions with high precision.
许多大型研究都采用腕部或大腿加速度计来捕捉身体活动，但这些测量方法来推断活动能量消耗（AEE），进而推断总能量消耗（TEE）的准确性尚未得到证实。本研究的目的是评估在自由生活条件下，使用金标准标准，腕部和大腿部位的加速度强度作为 AEE 和 TEE 估计值的有效性。
对 193 名英国成年人（男性 105 名，女性 88 名，年龄 40-66 岁，BMI 20.4-36.6kg/m2）进行了三轴加速度计的测量，在自由生活条件下佩戴在优势手腕、非优势手腕和大腿上，持续 9-14 天。在一个亚样本（男性 50 名，女性 50 名）中，同时使用双标记水（DLW）评估 TEE。使用既定的估算模型从非优势手腕估算 AEE，并在非 DLW 亚样本中为优势手腕和大腿推导出新模型。通过平均偏差、均方根误差（RMSE）和 Pearson 相关系数评估与 DLW 的 AEE 和 TEE 的一致性。
来自 DLW 的平均 TEE 和 AEE 分别为 11.6（2.3）MJ/天和 49.8（16.3）kJ/天/kg。优势手腕和非优势手腕在自由生活中的加速度高度相关（r=0.93），但与大腿的相关性较低（r=0.73 和 0.66）。来自优势手腕的 AEE 估算值为 48.6（11.8）kJ/天/kg，非优势手腕为 48.6（12.3）kJ/天/kg，大腿为 46.0（10.1）kJ/天/kg；这些与 AEE （RMSE12.2kJ/天/kg，r0.71）高度一致，且在人群水平上的平均偏差较小（6%）。只有大腿的估计值在统计学上与标准值有显著差异。当将这些 AEE 估计值与估算的 REE 相结合时，与标准值的一致性更强（RMSE1.0MJ/天，r~0.90）。
在英国成年人中，腕部或大腿测量的加速度可以用于在自由生活条件下以高精度估计人群水平的 AEE 和 TEE。
