Does performing moderate-to-vigorous physical activity in 12 to 24 hours prior Bioelectrical Impedance Analysis affects the validity of body water compartments assessment?

Purpose: One of the bioelectrical impedance spectroscopy (BIS) requirement is to avoid performing physical activity in the 12-24h prior measurement, which can be difficult in highly active populations. This investigation aimed: to examine if moderate to vigorous physical activity (MVPA) performed in 12-24h prior BIS testing, affects the validity of determining total body water (TBW), extracellular water (ECW) and intracellular water (ICW) using dilution techniques as the reference method. Methods: Twenty-seven healthy highly active males, aged 20 to 39 years (72.4 ± 8.7 Kg;1.77 ± 0.07 m) were evaluated. BIS and dilution techniques were used to assess TBW, ECW, and ICW. Pearson coefficient of correlation was used to analyze if MVPA was associated with the difference between methods for TBW, ECW, and ICW. Results: No significant differences between BIS and the dilution technique for TBW, ECW, and ICW volumes were observed (p>0.05). For all water compartments, no association was found between MVPA in the previous 12-24h with the differences between methods (p>0.05). Conclusion: This study showed that performing MVPA 12-24h prior measuring water compartments may not compromise a valid estimation of TBW, ECW, and ICW from BIS compared to dilution techniques. Indeed, the magnitude of the differences between methods in body water assessment was not related with the amount of MVPA performed by highly active adults.Objetivo: Um dos requisitos de bioimpedância elétrica por espectroscopia prende-se com evitar a prática de atividade física nas 12-24h antes da medição, o que pode ser difícil em populações altamente ativas. Esta investigação teve como objetivo: examinar se a atividade física moderada a vigorosa (AFMV) realizada entre 12-24h antes do teste de bioimpedância elétrica por espectroscopia afeta a validade da determinação da água corporal total (ACT), água extracelular (AEC), e água intracelular (AIC) usando técnicas de diluição como o método de referência. Métodos: Foram avaliados vinte e sete homens saudáveis, altamente ativos, com idades entre os 20 e os 39 anos (72,4 ± 8,7Kg; 1,77 ± 0.07m). A bioimpedância elétrica por espectroscopia e as técnicas de diluição foram usadas para avaliar TBW, ECW e ICW. O coeficiente de correlação de Pearson foi usado para analisar se a AFMV estava associada à diferença entre os métodos para ACT, AEC e AIC. Resultados: Não foram observadas diferenças significativas entre a bioimpedância elétrica por espectroscopia e a técnica de diluição para os volumes ACT, AEC e AIC (p> 0,05). Para todos os compartimentos de água, não foi encontrada associação entre AFMV com as diferenças entre os métodos (p> 0,05). Conclusões: O presente estudo mostrou que a realização de AFMV 12-24h antes da medição dos compartimentos de água poderá não comprometer uma estimativa válida de ACT, AEC e AIC do BIS em comparação com as técnicas de diluição. De fato, a magnitude das diferenças entre os métodos na avaliação da água corporal não demonstrou associação com a quantidade de AFMV realizada por adultos altamente ativos

Bioelectrical impedance vector analysis (BIVA) in sport and exercise: Systematic review and future perspectives

Background Bioelectrical impedance vector analysis (BIVA) is a general concept that includes all methodologies used in the analysis of the bioelectrical vector, whereas the "classic" BIVA is a patented methodology included among these methods of analysis. Once this was clarified, the systematic review of the literature provides a deeper insight into the scope and range of application of BIVA in sport and exercise. Objective The main goal of this work was to systematically review the sources on the applications of BIVA in sport and exercise and to examine its usefulness and suitability as a technique for the evaluation of body composition, hydration status, and other physiological and clinical relevant characteristics, ultimately to trace future perspectives in this growing area, including a proposal for a research agenda. Methods Systematic literature searches in PubMed, SPORTDiscus and Scopus databases up to July, 2017 were conducted on any empirical investigations using phase-sensitive bioimpedance instruments to perform BIVA within exercise and sport contexts. The search included healthy sedentary individuals, physically active subjects and athletes. Result Nineteen eligible papers were included and classified as sixteen original articles and three scientific conference communications. Three studies analysed short-term variations in the hydration status evoked by exercise/training through whole-body measurements, eleven assessed whole-body body composition changes induced by long-term exercise, four compared athletic groups or populations using the whole-body assessment, and two analysed bioelectrical patterns of athletic injuries or muscle damage through localised bioimpedance measurements. Conclusions BIVA is a relatively new technique that has potential in sport and exercise, especially for the assessment of soft-tissue injury. On the other hand, the current tolerance ellipses of “classic” BIVA are not a valid method to identify dehydration in individual athletes and a new approach is needed. “Specific” BIVA, a method which proposes a correction of bioelectrical values for body geometry, emerges as the key to overcome “classic” BIVA limitations regarding the body composition assessment. Further research establishing standardised testing procedures and investigating the relationship between physiology and the bioelectrical signal in sport and exercise is needed. © 2018 Castizo-Olier et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Scopu

Strength, water compartments and phase angle in breast cancer survivors

Background: Accurate prognostic tools are determinant for decision-making in cancer care planning. Objective measures such as bioelectrical impedance spectroscopy (BIS) may improve the accuracy of prognostic. In this cross-sectional study the goal was to determine if the water compartments and the phase angle were predictors of muscular strength in breast cancer survivors (BCS). Methods: A total of 41 BCS (age 54.6 ± 9.2) were evaluated. Water compartments and phase angle were assessed with BIS and muscular strength was assessed with handgrip dynamometer. Moderate-to-vigorous physical activity (MVPA) was assessed using the International Physical Activity Questionnaire (IPAQ). Measurements were performed in the morning after an overnight feast. Results: Linear regression analysis showed that phase angle explained 22% (r2 = 0.216) of the variance of the handgrip. Independently of MVPA and time post-operation, phase angle remained a significant predictor (B=2.269, p=0.085). No associations were found between water compartments and handgrip strength (p>0.05). Conclusions: The findings of this study suggest that phase angle is an important predictor of muscular strength in breast cancer survivors.Introdução: É necessário definir medidas de prognóstico precisas para que haja uma melhor tomada de decisão relativamente ao planeamento do tratamento de cancro da mama. Medidas objetivas como a bioimpedância elétrica multiespectral (BIS) podem melhorar a precisão de prognóstico. Neste estudo transversal o objetivo será determinar se os compartimentos hídricos e o ângulo de fase são preditores da força muscular em sobreviventes de cancro da mama. Métodos: A amostra consistiu em 41 sobreviventes de cancro da mama (idade 54.6 ± 9.2 anos). Os compartimentos hídricos e o ângulo de fase foram medidos com a BIS e a força muscular com um dinamómetro. A atividade física moderada a vigorosa (MVPA) foi avaliada através do Questionário Internacional de Atividade Física (IPAQ). As medições foram realizadas durante a manhã com os participantes em jejum. Resultados: A análise da regressão linear mostra que o ângulo de fase explica 22% (r2 = 0.216) da variação da força muscular. Independentemente da MVPA e tempo pós-operatório, o ângulo de fase manteve-se um preditor significativo (B=2.269, p=0.085). Não foram encontradas associações entre os compartimentos hídricos e força muscular (p>0.05). Conclusão: Os resultados deste estudo sugerem que o ângulo de fase é um importante preditor da força muscular em sobreviventes de cancro da mama

Evaluation of Bioelectrical Impedance Spectroscopy for the Assessment of Extracellular Body Water

This study evaluates bioelectrical impedance spectroscopy (BIS) measurements to detect body fluid status. The multifrequency impedance measurements were performed in five female pigs. Animals were connected to an extracorporeal membrane oxygenation device during a lung disease experiment and fluid balance was recorded. Every 15 min the amount of fluid infusion and the weight of the urine drainage bag was recorded. From the fluid intake and output, the fluid balance was calculated. These data were compared with values calculated from a mathematical model, based on the extracellular tissue resistance and the Hanai Mixture theory. The extracellular tissue resistance was also measured with BIS. These experimental results strongly support the feasibility and clinical value of BIS for in vivo assessment of the hydration status

Impedance Analysis to Evaluate Nutritional Status in Physiological and Pathological Conditions

: A thorough knowledge of body composition assessment techniques is the cornerstone for initiating a customized nutritional program. The second step is to consider the potential of their application in different physiological and pathological conditions and their effectiveness in the management of a monitoring pathway during dietary interventions. To date, bioimpedance analysis is the most effective and reliable method for assessing body composition due to its advantages in terms of speed of execution, non-invasiveness and low cost. Therefore, this review article aims to analyze the main concepts and application areas of bioimpedance measurement techniques, in particular vector frequency-based analysis (BIVA) systems, in order to assess their validity in both physiological and pathological conditions

The application of biomedical engineering techniques to the diagnosis and management of tropical diseases: A review

This paper reviews a number of biomedical engineering approaches to help aid in the detection and treatment of tropical diseases such as dengue, malaria, cholera, schistosomiasis, lymphatic filariasis, ebola, leprosy, leishmaniasis, and American trypanosomiasis (Chagas). Many different forms of non-invasive approaches such as ultrasound, echocardiography and electrocardiography, bioelectrical impedance, optical detection, simplified and rapid serological tests such as lab-on-chip and micro-/nano-fluidic platforms and medical support systems such as artificial intelligence clinical support systems are discussed. The paper also reviewed the novel clinical diagnosis and management systems using artificial intelligence and bioelectrical impedance techniques for dengue clinical applications

Applications of bioelectrical impedance vector analysis (BIVA) in the study of body composition in athletes

Producción CientíficaThe study of body composition (BC) allows evaluating nutritional status, optimizing competitive performance, and monitoring the success of training regimens in athletes. Since BC reference techniques are expensive and/or invasive, in practice simpler, less expensive, and safer methods such as anthropometry are often used. The problem is that anthropometry requires a qualified anthropometrist, a rigorous measurement protocol using validated equipment, and a lengthy procedure because of its limited accuracy. Bioimpedance analysis (BIA) is an indirect method for estimating BC in a simple, fast, inexpensive, noninvasive, accurate, and reproducible manner. Despite the limitations of conventional BIA, it is still the most commonly used method for assessing BC in athletes. However, bioelectrical impedance vector analysis (BIVA) allows qualitative assessment of body cell mass (BCM) and hydration status without the need for biological assumptions and without being subject to conventional BIA errors. The purpose of this article was to demonstrate the uses and applications of BIA in the study of the BC and physical characteristics of athletes. For example, several practical cases of athletes from different sports were compared. The results obtained from somatotype studies, conventional BIA, and BIVA were included. BIVA interpretation and somatotype were consistent for all cases analyzed, but BIVA also provided information about hydration and BCM. The application of BIVA in the assessment of athletes can improve BC studies in sports because it is fast, simple, and reliable and neither imposes two-compartment-model limitations on BC estimation nor requires any biological assumptions

Phase angle in localized bioimpedance measurements to assess and monitor muscle injury

Localized bioimpedance (L-BIA) measurements are an innovative method to non-invasively identify structural derangement of soft tissues, principally muscles, and fluid accumulation in response to traumatic injury. This review provides unique L-BIA data demonstrating significant relative differences between injured and contralateral non-injured regions of interest (ROI) associated with soft tissue injury. One key finding is the specific and sensitive role of reactance (Xc), measured at 50 kHz with a phase-sensitive BI instrument, to identify objective degrees of muscle injury, localized structural damage and fluid accretion, determined using magnetic resonance imaging. The predominant effect of Xc as an indicator of severity of muscle injury is highlighted in phase angle (PhA) measurements. Novel experimental models utilizing cooking-induced cell disruption, saline injection into meat specimens, and measurements of changing amounts of cells in a constant volume provide empirical evidence of the physiological correlates of series Xc as cells in water. Findings of strong associations of capacitance, computed from parallel Xc (XCP), with whole body counting of 40-potassium and resting metabolic rate support the hypothesis that parallel Xc is a biomarker of body cell mass. These observations provide a theoretical and practical basis for a significant role of Xc, and hence PhA, to identify objectively graded muscle injury and to reliably monitor progress of treatment and return of muscle function.Peer ReviewedPostprint (author's final draft