Exercise performed before infections has been linked to improvement of the immune response against infections. The purpose of this study was to evaluate the influence of preinfection moderate-intensity treadmill training on acute Trypanosoma cruzi infection in mice. Ninety-nine female BALB/c mice were divided into 4 groups, as follows: training + infection (T+I) (n = 41); no training + infection (NT+I) (n = 38); training + no infection (T+NI) (n = 10); and no training + no infection (NT+NI) (n = 10). The exercise program for trained groups was carried out on a motorized treadmill for 8 weeks. Infected groups were inoculated with the Y strain of T. cruzi. Infectivity, prepatent period, patent period, parasitemia peak, mortality, survival time, weight, food intake, tumor necrosis factor-alpha serum levels, and peritoneal macrophage hydrogen peroxide production were evaluated. We found that preinfection training induced statistically significant reductions in parasitemia peak (p < 0.03) and weight loss (p < 0.04). However, no statistically significant differences were found for the other parameters evaluated when trained and nontrained infected groups were compared. We conclude that preinfection aerobic training induces some improvement in the immune response to T. cruzi infection in female BALB/c mice.

Gluconeogenesis overstimulation due to hepatic insulin resistance is the best-known mechanism behind elevated glycemia in obese subjects with hepatic steatosis. This suggests that glucose production in fatty livers may differ from that of healthy livers, also in response to other gluconeogenic determinant factors, such as the type of substrate and modulators. Thus, the aim of this study was to investigate the effects of these factors on hepatic gluconeogenesis in cafeteria diet-induced obese adult rats submitted to a cafeteria diet at a young age. The livers of the cafeteria group exhibited higher gluconeogenesis rates when glycerol was the substrate, but lower rates were found when lactate and pyruvate were the substrates. Stearate or glucagon caused higher stimulations in gluconeogenesis in cafeteria group livers, irrespective of the gluconeogenic substrates. An increased mitochondrial NADH/NAD⁺ ratio and a reduced rate of ¹⁴CO₂ production from [¹⁴C] fatty acids suggested restriction of the citric acid cycle. The higher glycogen and lipid levels were possibly the cause for the reduced cellular and vascular spaces found in cafeteria group livers, likely contributing to oxygen consumption restriction. In conclusion, specific substrates and gluconeogenic modulators contribute to a higher stimulation of gluconeogenesis in livers from the cafeteria group.

The aim of the study was to analyse the relationship between running performance and passes, as well as the effect of substitutions and the competitive level on these variables, during official futsal matches. Male juvenile athletes were filmed during five official games in the Youth Games competition and adult athletes were monitored during National League. The athletes were tracked to obtain their trajectories for subsequent quantification of physical actions, number of substitutions and passes during the games. Impairment in running performance, number of passes and number of substitutions were recorded using video cameras and analysed on a computer-based tracking system. The number of substitutions contributed singly to increasing total distance covered, very high-intensity running (%VHIR), and certain passes, regardless of possible differences between under 17 and adult categories. Players with a decrease in %VHIR presented lower (p = 0.039) pass efficiency (4% below). The adult players demonstrated that drop in running performance and successful passes in a futsal game may be observed from the second quarter, not only in the second half as shown in previous studies in futsal. Substitution of players is an important strategy to be used by coaches to improve running performance and passes in futsal games.

INTRODUÇÃO: A doença de Chagas é uma infecção causada pelo Trypanosoma cruzi que afeta oito milhões de pessoas na América Latina. Um fator ligado ao estilo de vida que interfere significativamente na resposta à infecção é o exercício físico, dependendo do tipo, intensidade e frequência da atividade praticada. OBJETIVO: Avaliar a influência do exercício físico aeróbio moderado crônico pré-infecção na evolução da infecção experimental pelo T. cruzi em camundongos de duas linhagens distintas pertencentes aos dois sexos. MÉTODOS: Camundongos Swiss e BALB/c (machos e fêmeas) com 30 dias de idade foram divididos em quatro grupos para cada linhagem e sexo (total de 16) e nomeados como segue: SM (Swiss machos), SF (Swiss fêmeas), BM (BALB/c machos) e BF (BALB/c fêmeas). Os grupos foram: NT+NI (não treinado+não infectado), T+NI (treinado+não infectado), NT+I (não treinado+infectado) e T+I (treinado+infectado). O programa de exercício físico aeróbio moderado crônico pré-infecção foi realizado durante oito semanas, com uma sessão diária de treinamento, cinco vezes na semana. O inóculo foi de 1.400 tripomastígotas sanguíneos da cepa Y do T. cruzi, via intraperitoneal. Foi avaliado o pico de parasitos, parasitemia total média e as medidas das atividades séricas de CK e CK-MB. RESULTADOS E CONCLUSÃO: O treinamento físico promoveu nas duas linhagens e em ambos os sexos redução no pico de parasitos e na parasitemia total média em animais infectados pelo T. cruzi. O treinamento físico promoveu redução nas atividades séricas de CK e CK-MB em animais infectados pelo T. cruzi, de ambos os sexos, das duas linhagens, exceto para fêmeas Swiss na atividade de CK e CK-MB.