Rudnev Sergey

Introduction. Bioelectrical impedance analysis (BIA) is an indirect method of body composition assessment. The equipment for BIA measurements is produced in many countries including Russia and may differ in electrical current frequencies, measurement schemes and built-in algorithms for the evaluation of body composition. In view of this, body composition estimates from various BIA instruments may be inconsistent which limits the ability to combine and generalize BIA data. Our purpose was to analyze the consistency and possibility of joint use of the BIA data obtained using the ABC-01 ‘Medas’ (SRC Medas, Moscow) and Diamant-AIST (LLC Diamant, St. Petersburg) instruments in adults.

Materials and methods. 185 adult volunteers (107 women and 78 men) aged 18 to 61 years were examined according to the standard anthropometric measurement protocol and on the basis of paired consecutive measurements with the bioimpedance body composition instruments ABC-01 ‘Medas’ and Diamant-AIST. The estimates of fat-free mass (FFM), body fat (BF) and percentage body fat (%BF) were compared. Mutual calibration of the bioimpedance data was carried out based on transformation of the Diamant-AIST data using a conversion formula between the ABC-01 ‘Medas’ and Diamant-AIST resistances and subsequent application the ABC-01 ‘Medas’ body composition assessment algorithm.

Results. There were significant differences in the median values of FFM, BF and %BF estimates provided by the ABC-01 ‘Medas’ and Diamant-AIST instruments. The FFM values in females using the ABC-01 ‘Medas’ instrument were significantly lower, and the BF and %BF were significantly higher as compared to the Diamant-AIST data. In males, the inverse relationship was observed while maintaining significant differences between the medians.

The differences in paired estimates of body composition data provided by the ABC-01 ‘Medas’ instrument and the transformed Diamant-AIST data in males and females, respectively, were statistically insignificant. Also, the confidence intervals for the differences of paired body composition estimates reduced essentially, but still not ensured good consistency of individual body composition data.

Conclusions. Significant differences in paired values of fat-free mass, fat mass and relative body fat using the ABC-01 ‘Medas’ and Diamant-AIST bioimpedance instruments are obtained. The possibility of mutual calibration and joint analysis of the related bioimpedance data at the group level is established. © 2023. This work is licensed under a CC BY 4.0 license.

Introduction. Due to the wide variety of ethnogeographic features and ecological niches, environmental differences as well as changes in living conditions, the study of the morphological status of indigenous populations of Russia retains its significance. Our aim was to study the somatic status and BIA body composition of young women of Altai and Russian ethnicities aged 17-23 years living in urban and rural areas of the Altai Republic.

Materials and methods. In 2021–2023, 230 young women aged 17 to 23 years (117 Altai-Kizhi and 113 Russians) living in urban and rural areas were examined. The examination program included anthropometry, the Heath-Carter somatotyping, and BIA. Ethnic differences and city-village differences were assessed using parametric and non-parametric methods.

Results. Ethnically Russian women were, in general, somewhat larger than Altai women, significant differences were found for height (Ht), weight (Wt), waist circumference (WC) and waist-to-hip ratio (WHR). Significant differences were also observed for the resistance R50, phase angle and fat-free mass (FFM) values. The somatotype distributions by enlarged classes were close with a predominance of mesomorphic and endomorphic types. When testing for city-village differences in ethnic subgroups, the total body dimensions (Wt, Ht, chest circumference), as well as WC, hip circumference (HC) and body mass index were slightly higher in urban residents (not significant differences). The urban Altai women had a statistically significantly higher endomorphy rating with a noticeable increase in fat mass (FM), %FM and fat mass index. Ethnic differences were more pronounced in rural (Ht, Wt, HC, WHR, R50, phase angle, FFM and fat-free mass index were significantly different) than in urban residents (significant differences only for Ht and FFM).

Conclusions. The results of our study suggest that permanent residence in urban or rural areas, along with ethnic differences, is a significant factor associated with the somatic status of young Altai-Kizhi and ethnically Russian women belonging to the modern indigenous population of the Altai Republic. In the subgroup of young women who are inherently living in the city, less pronounced ethnic differences in somatic status were observed as compared to residents of rural areas. © 2024. This work is licensed under a CC BY 4.0 license.

Introduction. In recent years, laser-based rangefinders have been considered as a possible alternative to mechanical anthropometers. One of these instruments is the KAFA-Laser anthropometer (KAFA, Russia). Our aim was to test the accuracy and reproducibility of the KAFA-Laser anthropometer when measuring height of anthropometric points.

Materials and methods. Using anthropometers GPM (DKSH, Switzerland) and KAFA-Laser, paired measurements of the height of 9 anthropometric points were carried out on 10 males aged 18-47 years. The measurements were performed by 3 researchers having different experience, 3 times in succession. The accuracy of measurements with the KAFA-Laser instrument was assessed by comparison with the GPM data. Intergroup differences were assessed using Wilcoxon signed rank test. Technical measurement errors and reliability coefficients were assessed.

Results and discussion. The difference in the height of anthropometric points when measured with the KAFA-Laser and GPM anthropometers significantly depended on the qualification of the measurers and was minimal (+0.0-0.5 cm) for researcher 1, a more experienced user of the KAFA-Laser anthropometer (absence of significant differences for 7 out of 9 points). The mean standard deviations for researcher 1 were lower than those for researchers 2 and 3 and were consistent with traditional anthropometry. Measurements with the GPM anthropometer showed lower individual, inter-individual, and total technical errors. Measurements of the vertex point were characterized by low values of technical measurement errors and high coefficients of reliability (0.94 and 0.95, respectively), and for the remaining points varied widely, which indicates the relevance of implementing objective quality control of anthropometric measurements.

Conclusion. The results of testing KAFA-Laser anthropometer suggest the possibility of obtaining comparable results of measurements of the height of anthropometric points in terms of accuracy and reproducibility to that of the conventional anthropometry with the proper level of mastery of the measurement techniques. © 2024. This work is licensed under a CC BY 4.0 license