André de Camargo Smolarek

HIGH DOSES OF SODIUM BICARBONATE INCREASE LACTATE LEVELS AND DELAY EXHAUSTION IN A CYCLING PERFORMANCE TEST

OBJECTIVES It is well established that ingestion of sodium bicarbonate (NaHCO3) causes metabolic alkalosis. However, there is no consensus in terms of optimal NaHCO3 doses leading to enhanced performance. This study aimed to determine the effects of different NaHCO3 doses on performance and lactate clearance in non-professional cyclists. METHODS Twenty-one cyclists performed the following three double-blind trials: 1) ingestion of 0.3 g · kg-1 body weight (BW) of placebo; 2) ingestion of 0.1 g · kg-1 BW NaHCO3 plus 0.2 g · kg-1 BW placebo (0.1 BC); and 3) ingestion of 0.3 g · kg-1 BW NaHCO3 (0.3 BC). Performance was evaluated after warm-up on the bike followed by a performance test until exhaustion. Lactate levels were monitored in blood samples before and immediately after performance tests. RESULTS Lactate levels in the blood were significantly higher after exercise in 0.3 BC and 0.1 BC (15.12 ± 0.92 versus 10.3 ± 1.22 and 13.24 ± 0.87 versus 10.3 ± 1.22 mmol/L; P < 0.05) compared with control. Significant improvements in performance were only identified in 0.3 BC group (76.42 ± 2.14; P = 0.01). CONCLUSIONS The present study found that 0.3 g · kg-1 BW NaHCO3 is effective in improving performance and improving blood lactate levels in cyclists compared with control and 0.1 g · kg-1 BW NaHCO3.

ASSOCIAÇÃO DO PERFIL GLICÊMICO COM ESTADO NUTRICIONAL E PRESSÃO ARTERIAL SISTÊMICA DE ADOLESCENTES

Introduction: Overweight and obesity are related to changes in blood glucose and blood pressure. However, this association has not been well established in adolescents. Objective: Investigate the association of nutritional status, blood pressure, and glycemic profile of adolescents. Patients and Methods: This is a pediatric cross-sectional study carried out in the city of Curitiba, Parana, Brazil. Study sample was composed of 391 adolescents. Nutritional status was diagnosed using weight and height to calculated body mass index. The adolescents with a percentile > 85 were considered overweight and those with the percentile > 95 were considered obese. Blood pressure was measured using a mercury sphygmomanometer in a single moment. The cutoff point for hypertension was systolic blood pressure and/or diastolic ≥ 95th percentile. Fasting glycemia was measured using a glucose meter. It was considered altered when values were greater than 100 mg/dL. Results: The prevalence of abnormal glucose was 29.7% for boys and 32.4% for the girls. There was a strong association (OR = 4.2; 95% CI 1.37, 12.86) between altered glycemia and systolic blood pressure in male students. Conclusion: This study highlights the importance of monitoring these risk factors in young Brazilians, as well as interventions to encourage physically active behavior and a healthier diet.

Prevalência de síndrome metabólica em meninos de 10 a 18 anos na cidade de curitiba

The objective of this study was to determine the prevalence of metabolic syndrome in adolescents aged 10 to 18 years in the Curitiba city. The sample consisted of 79 boys in the public schools of the city of Curitiba. Waist circumference was measured, lipid and glycemic profile criteria were then used to determine the prevalence of metabolic syndrome. The statistics used were mean, standard deviation and frequency percentile. The results were that the boys have changed values of CA = 10.1%, hypertension = 1.3%, glucose = 30.4%, 49.4% = Total Cholesterol, HDL = 35.4%, LDL = 43 Triglycerides =% and 16.5%. With these data we observed that 26.6% of subjects had metabolic syndrome. We conclude that there is an prevalence of 26% of metabolic syndrome in adolescent boys from the city of Curitiba-PR.

Efeitos de duas intensidades de treinamento aeróbio na composição corporal e na potência aeróbia e anaeróbia de meninos pré-púberes

O proposito do estudo foi verificar os efeitos de duas intensidades de treinamento aerobio sobre a composicao corporal, potencia aerobia e anaerobia de meninos pre-puberes. Fizeram parte da amostra 35 criancas, 12 meninos realizaram o treinamento com intensidade igual ou superior a 70% da frequencia cardiaca reserva (GA); 12 meninos realizaram treinamento com intensidade igual a 50% da frequencia cardiaca reserva (GB); grupo controle (GC) foi formado por 11 meninos, os quais foram estimulados a manterem suas atividades diarias normais. Foram realizadas medidas de massa corporal, estatura, dobras cutâneas do triceps e panturrilha para determinacao do percentual de gordura e nivel de atividade fisica habitual por meio de questionario desenvolvido por Bouchard. A potencia aerobia foi mensurada atraves do teste de vai-e-vem de 20 m e a anaerobia pelo teste de Wingate. Observando os resultados, o treinamento aerobio mais intenso (70% da FC de reserva), nao apresentou modificacao no percentual de gordura e nem aumento da potencia anaerobia, contudo, a potencia aerobia se elevou significativamente (p < 0,05) em relacao aos outros grupos. Independente do nivel de atividade fisica, somente o treinamento de alta intensidade foi capaz de melhorar a potencia aerobia de meninos pre-puberes.