Exercise and Health Laboratory, CIPER, Faculdade Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal.
Pennington Biomedical Research Foundation, Baton Rouge, LO, USA.
Scand J Med Sci Sports. 2021 Aug;31(8):1612-1620. doi: 10.1111/sms.13966. Epub 2021 Apr 13.
We aimed to validate bioelectrical impedance spectroscopy (BIS), compared with tracer dilution measurements, for assessing total body water (TBW), intracellular water (ICW), and extracellular water (ECW) in athletes differing in hydration status. A total of 201 athletes participated. Reference TBW and ECW were determined by deuterium and bromide dilution methods, respectively; ICW was calculated as TBW-ECW. Water compartments were estimated by BIS. Urine specific gravity (USG) classified athletes into well-hydrated (WH) (USG < 1.023), euhydrated (EH) (USG:1.024-1.026), and dehydrated (DH) (USG>1.027). No significant differences were found between BIS and the reference methods for WH, EH, and DH athletes for TBW, ICW nor ECW (p>0.05). Concordance of TBW and its compartments by method was significant (p < 0.001) with coefficients of determination ranging by hydration classification [EH:52-96%;DH:56-98%;WH:71-96%]. Bland-Altman analyses showed no trend for TBW and its compartments with the exception of ICW in the WH athletes. The 95% confidence BIS intervals for the WH group ranged from -3.08 to 2.68 kg for TBW, -4.28 to 4.14 kg for ICW, and -3.29 to 3.02 kg for ECW. For the EH athletes, the 95% confidence intervals ranged from -2.78 to 2.24 kg for TBW, -4.10 to 3.94 kg for ICW, and -3.44 to 3.06 kg for ECW. In DH group, TBW ranged between -1.99 and 2.01 kg, ICW between -3.78 and 6.34 kg, and ECW between -6.22 and 3.74 kg. These findings show that BIS is useful at a group level in assessing water compartments in athletes differing in hydration status. However, the usefulness of BIS is limited at an individual level, especially in dehydrated athletes.
我们旨在通过与示踪稀释测量法比较，验证生物电阻抗谱（BIS）评估不同水合状态运动员的总体水（TBW）、细胞内水（ICW）和细胞外水（ECW）。共有 201 名运动员参与了研究。TBW 和 ECW 分别通过氘和溴化物稀释方法确定，ICW 则为 TBW-ECW。BIS 用于估计水室。尿比重（USG）将运动员分为水合良好（WH）（USG<1.023）、水合正常（EH）（USG：1.024-1.026）和脱水（DH）（USG>1.027）。对于 WH、EH 和 DH 运动员，BIS 与参考方法在 TBW、ICW 和 ECW 方面均无显著差异（p>0.05）。通过方法确定的 TBW 及其各部分的一致性具有显著意义（p<0.001），且决定系数因水合分类而异[EH：52-96%；DH：56-98%；WH：71-96%]。Bland-Altman 分析表明，TBW 及其各部分除 WH 运动员的 ICW 外，无趋势变化。WH 组的 BIS 95%置信区间范围为 TBW 为-3.08 至 2.68kg，ICW 为-4.28 至 4.14kg，ECW 为-3.29 至 3.02kg。EH 运动员的 95%置信区间范围为 TBW 为-2.78 至 2.24kg，ICW 为-4.10 至 3.94kg，ECW 为-3.44 至 3.06kg。DH 组中，TBW 范围在-1.99 至 2.01kg 之间，ICW 在-3.78 至 6.34kg 之间，ECW 在-6.22 至 3.74kg 之间。这些发现表明，BIS 在评估不同水合状态运动员的水室方面在群体水平上是有用的。然而，BIS 在个体水平上的有用性有限，尤其是在脱水运动员中。
