3DNX 加速度计在机械和人体跑步机运动测试中的可靠性和有效性。

Reliability and validity of the 3DNX accelerometer during mechanical and human treadmill exercise testing.

机构信息

Department for Health, Sport Health and Exercise Science, University of Bath, UK.

出版信息

Int J Obes (Lond). 2011 Apr;35 Suppl 1:S88-97. doi: 10.1038/ijo.2011.39.

DOI:10.1038/ijo.2011.39

PMID:21483427

Abstract

OBJECTIVE

This study aimed to assess the validity and reliability of the 3DNX triaxial accelerometer in a laboratory and mechanical setting.

METHODS

Experiment 1: A total of 10 units were fixed to a Multi-axis shaker table. A schedule comprising a range of accelerations was repeated on two occasions along each of the three measurement axes. Experiment 2: A total of 11 recreationally active individuals completed a treadmill protocol (4-20 km hr(-1)) on two occasions. Two 3DNX accelerometers were secured to the lower back, logging data every 5 s. Oxygen uptake was measured using the Douglas Bag technique. Reliability inter- and intra-units were assessed using a combination of limits of agreement (LoA), coefficient of variation (CV) and intra-class correlation coefficient (ICC). Validity was assessed using simple linear regression. All data are expressed in counts per 5 s (counts 5 s(-1)).

RESULTS

Experiment 1: CV(intra) ranged from 0.0 to 8.9% in all axes. The absolute bias±95% LoA values were all below four counts 5 s(-1). CV(inter) did not rise above 4.5%. ICCs were 1.0 for all stages in all axes. The relationship between 3DNX counts and acceleration yielded an R(2) value of 0.99 and a standard error of the estimate (SEE) of six counts 5 s(-1). Experiment 2: CV(inter) ranged from 7.7 to 16.0% for trial 1 and from 7.7 to 16.2% for trial 2. ICCs between units ranged from 0.95 to 1.00 for trial 1 and from 0.90 to 0.99 for trial 2. Mean ratio bias±95% LoA values for intra-unit and inter-unit reliability were -0.7% (P>0.05)±12.4% and 0.4% (P>0.05)±5.6%, respectively. The relationship between VO(2) and 3DNX counts for walking and running was linear (R(2)=0.65, SEE=1.42 ml kg(-1) min(-1); R(2)=0.62, SEE=3.63 ml kg(-1) min(-1)).

CONCLUSION

The 3DNX accelerometer is a reliable and valid device for measuring acceleration in a mechanical setting and during human treadmill exercise.

摘要

目的

本研究旨在评估 3DNX 三轴加速度计在实验室和机械环境中的有效性和可靠性。

方法

实验 1：将总共 10 个单元固定在多轴振动台上。沿着三个测量轴的每一个，重复了一个包括一系列加速度的方案两次。实验 2：总共 11 名休闲活跃的个体在两次完成跑步机方案（4-20 公里/小时）。将两个 3DNX 加速度计固定在腰部，每 5 秒记录一次数据。使用 Douglas 袋技术测量耗氧量。使用一致性限（LoA）、变异系数（CV）和组内相关系数（ICC）的组合评估单元内和单元间的可靠性。使用简单线性回归评估有效性。所有数据均以每秒 5 次计数（计数 5 s(-1)）表示。

结果

实验 1：所有轴的 CV(intra) 范围为 0.0 至 8.9%。绝对偏差±95% LoA 值均低于四个计数 5 s(-1)。CV(inter) 不超过 4.5%。所有轴的所有阶段的 ICC 均为 1.0。3DNX 计数与加速度之间的关系得出 R(2) 值为 0.99，估计标准误差（SEE）为 6 个计数 5 s(-1)。实验 2：试验 1 的 CV(inter) 范围为 7.7%至 16.0%，试验 2 的 CV(inter) 范围为 7.7%至 16.2%。单元间的 ICC 范围为试验 1 的 0.95 至 1.00 和试验 2 的 0.90 至 0.99。内单元和单元间可靠性的平均比值偏差±95% LoA 值分别为-0.7%（P>0.05）±12.4%和 0.4%（P>0.05）±5.6%。步行和跑步时 VO(2)与 3DNX 计数之间的关系是线性的（R(2)=0.65，SEE=1.42 ml kg(-1) min(-1)；R(2)=0.62，SEE=3.63 ml kg(-1) min(-1)）。