UCT/MRC Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town and Sports Science Institute of South Africa, Boundary Road, Newlands, 7700, South Africa,
Eur J Appl Physiol. 2014 May;114(5):941-50. doi: 10.1007/s00421-014-2825-x. Epub 2014 Jan 30.
We investigated the accuracy of the Moxus Modular Metabolic System (MOXUS) against the Douglas Bag Method (DBM) during high-intensity exercise, and whether the two methods agreed when detecting small changes in [Formula: see text] between two consecutive workloads ([Formula: see text]).
Twelve trained male runners performed two maximal incremental running tests while gas exchange was analyzed simultaneously by the two systems using a serial setup for four consecutive intervals of 30 s on each test. Comparisons between methods were performed for [Formula: see text], [Formula: see text], fractions of expired O2 (FeO2) and CO2 (FeCO2) and [Formula: see text].
The MOXUS produced significant higher (mean ± SD, n = 54) readings for [Formula: see text] (80 ± 200 mL min(-1), p = 0.005) and [Formula: see text] (2.9 ± 4.2 L min(-1), p < 0.0001), but not FeO2 (-0.01 ± 0.09). Log-transformed 95 % limits of agreement for readings between methods were 94-110 % for [Formula: see text], 97-108 % for [Formula: see text] and 99-101 % for FeO2. [Formula: see text] for two consecutive measurements was not different between systems (120 ± 110 vs. 90 ± 190 mL min(-1) for MOXUS and DBM, respectively, p = 0.26), but agreement between methods was very low (r = 0.25, p = 0.12).
Although it was tested during high-intensity exercise and short sampling intervals, the MOXUS performed within the acceptable range of accuracy reported for automated analyzers. Most of the differences between equipments were due to differences in [Formula: see text]. Detecting small changes in [Formula: see text] during an incremental test with small changes in workload, however, might be beyond the equipment's accuracy.
我们研究了 MOXUS 模块化代谢系统（MOXUS）在高强度运动中与 Douglas 袋法（DBM）相比的准确性，以及当在两次连续负荷之间检测到 [Formula: see text] 的微小变化时，两种方法是否一致。
12 名经过训练的男性跑步者在两次最大增量跑步测试中同时进行，使用串行设置，在每次测试的四个连续 30 秒间隔内同时使用两种系统分析气体交换。方法之间的比较是针对 [Formula: see text]、[Formula: see text]、呼出氧气（FeO2）和二氧化碳（FeCO2）的分数和 [Formula: see text] 进行的。
MOXUS 产生了显著更高的（平均值±标准差，n = 54）[Formula: see text]（80 ± 200 mL min(-1)，p = 0.005）和 [Formula: see text]（2.9 ± 4.2 L min(-1)，p < 0.0001）读数，但 FeO2 除外（-0.01 ± 0.09）。两种方法之间读数的 95%一致性限制范围为 [Formula: see text]为 94-110%，[Formula: see text]为 97-108%，FeO2 为 99-101%。两种系统连续两次测量的 [Formula: see text] 没有差异（MOXUS 和 DBM 分别为 120 ± 110 和 90 ± 190 mL min(-1)，p = 0.26），但两种方法之间的一致性非常低（r = 0.25，p = 0.12）。
尽管它在高强度运动和短采样间隔下进行了测试，但 MOXUS 的性能在报告的自动分析仪的可接受精度范围内。设备之间的大多数差异是由于 [Formula: see text] 的差异造成的。然而，在增量测试中，当工作负荷有较小变化时，检测到 [Formula: see text] 的微小变化，可能超出了设备的精度范围。
