ABSTRACT
Trata-se de um estudo longitudinal e observacional que investigou as consequências do lockdown em decorrência do coronavírus em 2020, na aptidão física relacionada à saúde e respostas bioquímicas de 16 adolescentes do sexo masculino com sobrepeso ou obesidade (idade 12,6 ± 1,8 anos). A antropometria, composição corporal, testes de aptidão física e medidas de biomarcadores sanguíneos (glicemia em jejum, colesterol total [CT], colesterol de lipoproteína de baixa densidade [LDL-c], triglicerídeos [TG], aspartato aminotransferase [AST] e alanina aminotransferase [ALT]) foram avaliados antes e após 8 meses de lockdown. Os resultados mostraram um aumento do peso corporal, massa livre de gordura e circunferência da cintura e do quadril (p<0,05) após 8 meses. A força isométrica máxima de preensão manual e a flexibilidade aumentaram, enquanto a resistência muscular diminuiu (p<0,05). A glicemia em jejum, CT, LDL-c, TG, TG/glicose, AST, ALT, TG/HDL-c, CT/HDL-c e LDL/HDL aumentaram (p<0,05), ao passo que os níveis de HDL-c diminuíram significativamente (p<0,05). Portanto, 8 meses de isolamento social promoveram efeitos deletérios sobre parâmetros morfológicos e aptidão física em adolescentes. No entanto, o pequeno tamanho da amostra impede a generalização desses achados.
This longitudinal and observational study investigated the consequences of the coronavirus disease 2019 lockdown on health-related physical fitness and biochemical responses in 16 overweight or obese male adolescents (aged 12.6±1.8 years). The anthropometry, body composition, physical fitness tests, and measures of blood biomarkers (fasting blood glucose, total cholesterol [TC], low-density lipoprotein cholesterol [LDL-c], triglycerides [TG], aspartate aminotransferase [AST], and alanine aminotransferase [ALT]) were evaluated before and after 8 months of lockdown. The results showed increased body weight, fat-free mass, and waist and hip circumference (p<0.05) after 8 months. Maximum isometric handgrip strength and flexibility increased, while muscle endurance decreased (p<0.05). Fasting blood glucose, TC, LDL-c, TG, TG/glucose, AST, ALT, TG/HDL-c, CT/HDL-c, and LDL/HDL increased (p<0.05), while the HDL-c levels decreased significantly (p<0.05). Therefore, eight months of social isolation promoted harmful effects on adolescents' morphological parameters and physical fitness. However, the small sample size prevents the generalization of these findings.
ABSTRACT
SUMMARY: Previous evidence indicates that body fat can distinguish Brazilian jiu-jitsu (BJJ) athletes according to the competitive level. However, propositions of cut-off points for establishing classifications of body fat percentage for combat sports athletes and, specifically, for BJJ athletes are still incipient in the literature. In this sense, the main aim of the present study was to establish a normative table for the classification of body fat percentage in BJJ athletes. As a secondary aim, athletes were compared according to competitive level. Ninety male BJJ athletes (aged: 29.0 ± 8.2 years; practice time: 6.0 ± 2.1 years; body mass: 82.1 ± 12.7 kg; height: 175.9 ± 6.5 cm; fat mass: 16.0 ± 8.9 kg; bone mineral content: 3.7 ± 0.6 kg; muscle mass: 37.9 ± 5.4 kg; body fat percentage: 17.3 ± 6.8 %; basal metabolic rate: 1811.4 ± 193.4 kcal) from different competitive levels: state (n= 42), national (n= 26) and international (n= 22) took part in this study. All athletes had their body composition measured via tetrapolar bioelectrical impedance. Percentiles p10, p25, p50, p75, and p90 were used to establish the classification. As a result, the following classification was obtained: <7.7 % (very low); ≥7.7-11.5 % (low); 11.6-17.0 % (medium); 17.1-24.0 % (high) and ≥24.1 % (very high). State-level athletes had a higher fat percentage than national and international-level athletes (p<0.05). The proposed cut-off points can help professionals responsible for sports training and nutritional prescription in monitoring the body fat of BJJ athletes.
RESUMEN: La grasa corporal puede distinguir a los atletas de jiu-jitsu brasileño (BJJ) según el nivel competitivo. Sin embargo, las propuestas de puntos de corte para establecer clasificaciones de porcentaje de grasa corporal para deportistas de deportes de combate y, específicamente, para deportistas de BJJ son aún incipientes en la literatura. En este sentido, el objetivo principal del presente estudio fue establecer una tabla normativa para la clasificación del porcentaje de grasa corporal en atletas de BJJ. Secundariamente, comparar a los deportistas según el nivel competitivo. Participaron noventa atletas masculinos de BJJ (edad: 29,0 ± 8,2 años; tiempo de práctica: 6,0 ± 2,1 años; masa corporal: 82,1 ± 12,7 kg; estatura: 175,9 ± 6,5 cm; masa adiposa: 16,0 ± 8,9 kg; contenido mineral óseo: 3,7 ± 0,6 kg; masa muscular: 37,9 ± 5,4 kg; porcentaje de grasa corporal: 17,3 ± 6,8 %; tasa metabólica basal: 1811,4 ± 193,4 kcal) de diferentes niveles competitivos: estatal (n= 42), nacional (n= 26) e internacional (n= 22). Se evaluó la composición corporal a través de bioimpedancia tetrapolar. Para establecer la clasificación se utilizaron los percentiles p10, p25, p50, p75 y p90. Como resultado se obtuvo la siguiente clasificación: <7,7 % (muy bajo); ≥7,7-11,5 % (bajo); 11,6-17,0 % (medio); 17,1-24,0 % (alto) y ≥24,1 % (muy alto). Los atletas de nivel estatal tenían un porcentaje de grasa corporal más alto respecto a los atletas de nivel nacional e internacional (p <0.05). Los puntos de corte propuestos pueden ser útiles para monitorizar la grasa corporal de los atletas de BJJ.