Aptidão cardiorrespiratória, composição corporal e parâmetros bioquímicos em gêmeos monozigotos e dizigotos

Abstract

Introduction: The relationship between the cardiorespiratory optimum and body composition measures and biochemical variables is unknown, as well as the influence of genetic and environmental factors on this variable. In addition, there are few studies that use discordant twins for physical exercise. Aim: To evaluate cardiorespiratory fitness, body composition and biochemical parameters in concordant and discordant twin brothers for physical exercise. Methods: Cross-sectional study with adult twins. The sample consisted of 102 individuals, 72.5% female and 27.5% male, with a mean age of 25.4 ± 5.69. Data collection was carried out between the years 2016 and 2018. On day 1, individuals underwent an assessment of physical fitness, including anthropometric measures, body composition by X-ray double beam absorptiometry, and cardiorespiratory exercise test. On day 2, peripheral blood samples were collected to determine the lipid profile and fasting blood glucose. Spearman's correlation was used to verify heritability and to relate the variables to the cardiorespiratory optimal point. The monozygote twins were separated into three groups: active concordant twins, inactive concordant twins and discordant pairs for physical exercise. The ANOVA test (p <0.001) was used for analysis between the groups and the Wilcoxon test (p <0.05) for an intrapar analysis. Results: No associations were observed between the cardiorespiratory optimal point and body composition variables. The biochemical variables high-density lipoproteins, low-density lipoproteins, fasting glucose, and triglycerides showed a weak but significant correlation. Differences in body composition and cardiorespiratory variables were observed between the pairs of discordant twins and between the concordant groups. Conclusion: The Cardiorespiratory Optimal Point and the biochemical variables, showed a greater tendency to be influenced by environmental factors. Body composition, on the other hand, showed a greater influence of heritability and did not correlate with the cardiorespiratory optimum. In addition, the active twins had better values of body composition, VO2max and the second ventilatory threshold when compared to sedentary twins, however it was not possible to observe differences in lipid profile or fasting glucose in discordant monozygotic twins for physical exercise.