Campa Francesco, Matias Catarina N, Marini Elisabetta, Heymsfield Steven B, Toselli Stefania, Sardinha Luís B, Silva Analiza M
Int J Sports Physiol Perform. 2020 Mar 1;15(3):361-367. doi: 10.1123/ijspp.2019-0285.
To analyze the association between body fluid changes evaluated by bioelectrical impedance vector analysis and dilution techniques over a competitive season in athletes.
A total of 58 athletes of both sexes (men: age 18.7 [4.0] y and women: age 19.2 [6.0] y) engaging in different sports were evaluated at the beginning (pre) and 6 months after (post) the competitive season. Deuterium dilution and bromide dilution were used as the criterion methods to assess total body water (TBW) and extracellular water (ECW), respectively; intracellular water (ICW) was calculated as TBW-ECW. Bioelectrical resistance and reactance were obtained with a phase-sensitive 50-kHz bioelectrical impedance analysis device; bioelectrical impedance vector analysis was applied. Dual-energy X-ray absorptiometry was used to assess fat mass and fat-free mass. The athletes were empirically classified considering TBW change (pre-post, increase or decrease) according to sex.
Significant mean vector displacements in the postgroups were observed in both sexes. Specifically, reductions in vector length (Z/H) were associated with increases in TBW and ICW (r = -.718, P < .01; r = -.630, P < .01, respectively) and decreases in ECW:ICW ratio (r = .344, P < .05), even after adjusting for age, height, and sex. Phase-angle variations were positively associated with TBW and ICW (r = .458, P < .01; r = .564, P < .01, respectively) and negatively associated with ECW:ICW (r = -.436, P < .01). Phase angle significantly increased in all the postgroups except in women in whom TBW decreased.
The results suggest that bioelectrical impedance vector analysis is a suitable method to obtain a qualitative indication of body fluid changes during a competitive season in athletes.
通过生物电阻抗矢量分析和稀释技术，分析运动员在一个竞技赛季中体液变化之间的关联。
共有58名不同性别的运动员（男性：年龄18.7[4.0]岁，女性：年龄19.2[6.0]岁）参与不同运动项目，在赛季开始时（赛前）和赛季开始6个月后（赛后）接受评估。分别采用氘稀释法和溴化物稀释法作为评估总体水（TBW）和细胞外液（ECW）的标准方法；细胞内液（ICW）通过TBW-ECW计算得出。使用相敏50kHz生物电阻抗分析设备获取生物电阻和电抗；应用生物电阻抗矢量分析。采用双能X线吸收法评估脂肪量和去脂体重。根据性别，依据TBW变化（赛前-赛后，增加或减少）对运动员进行经验性分类。
在两个性别的赛后组中均观察到显著的平均矢量位移。具体而言，矢量长度（Z/H）的降低与TBW和ICW的增加相关（r = -0.718，P < 0.01；r = -0.630，P < 0.01），以及ECW:ICW比值的降低相关（r = 0.344，P < 0.05），即使在对年龄、身高和性别进行校正后也是如此。相角变化与TBW和ICW呈正相关（r = 0.458，P < 0.01；r = 0.564，P < 0.01），与ECW:ICW呈负相关（r = -0.436，P < 0.01）。除TBW降低的女性外，所有赛后组的相角均显著增加。
结果表明，生物电阻抗矢量分析是一种获取运动员在竞技赛季中体液变化定性指标的合适方法。
