This study was carried out to evaluate the creatine and maltodextrine dietetic supplementation of eventing horses. The experimental period consisted of 56 days, with 20 horses, which were randomly divided into four groups with different diets. Diets were: diet without supplement (Control); diet supplemented with creatine, 44.4 mg/kg body weight/day (20 g creatine/horse/day); diet supplemented with creatine, 88.8 mg/kg body weight/day (40 g creatine/horse/day); diet supplemented with maltodextrine, 222.2 mg/kg body weight/day (100 g/horse/day), during three days before each test. Every horse was submitted to three tests. Blood samples and heart rate were collected at rest, immediately after the tests and 10 and 20 minutes after the test. Supplementation with creatine (44.4 mg/kg body weight/day) and maltodextrine reduced plasma concentration of lactate in horses during tests. Supplementation of creatine and maltodextrine did not alter serum concentration of aspartate aminotransferase, γ-glutamyltransferase, urea or creatinine, but training affected blood biochemical variables in eventing horses.

Investigamos facetas do engajamento cognitivo, emocional e comportamental de um grupo de alunos de Ensino Médio, particularmente hábeis e empolgados durante a realização de uma atividade de investigação escolar. Coletamos os dados em uma sequência de quatro aulas de Física, gravadas em vídeo e áudio. Identificamos os períodos de maior atividade em torno dos desafios colocados pelo professor e as discussões que interferiam na condução da investigação. Analisamos interações entre os alunos com base nos conceitos psicanalíticos de "grupo de trabalho" e "suposições básicas". Aspectos da configuração do grupo e a qualidade das interações trouxeram implicações para seu desenvolvimento em diferentes dimensões. Verificamos que a situação de aprendizagem mobilizou múltiplos aspectos do engajamento dos alunos no nível da atividade e no nível da tarefa de aprendizagem. Concluímos que, sem o auxílio do professor, mesmo alunos hábeis e engajados ficam sujeitos a fugas inconscientes de tarefas de aprendizagem que exigem engajamento cognitivo.

We investigated facets of the cognitive, emotional and behavioral engagement of a group of secondary education students who were particularly clever and fascinated with investigational activity. Audio and video recordings were used to categorize the kind of involvement showed during the activity. The categories are inspired within a psychoanalytical frame of reference based on the concepts of work group and basic assumptions. Aspects of the group configuration and the quality of interactions have implications for development. We checked that the learning situation mobilized multiple aspects of the engagement of the students at the level of the activity and at the level of the learning task quality of the interactions. There are implications for development in different dimensions. We conclude that without the help of the teacher clever and committed students are subject to unconscious escapes from the learning task that demands cognitive engagement.