Bürger-Mendonça, Marcos
Graduado em Educação Física pela UNESA
RESUMO
O presente estudo teve como objetivo analisar a resposta do íon magnésio pré e pós-competição de triathlon em atletas do sexo masculino, na distância meio-ironman através da analise bioquímica da concentração do íon magnésio no plasma sangüíneo. Participaram do presente estudo 10 voluntários do sexo masculino fisicamente ativos, divididos em 2 grupos controle e experimental. Foram submetidos a duas coletas de aproximadamente 25 ml de sangue, após jejum de oito horas na posição sentada e imediatamente ao término da prova de cada atleta. Para análise estatística foi utilizado o software SPSS 11.0, para o teste T-student com a mesma amostra, tendo o valor de P<0.05 aceito como significante. Os valores após a competição entre o grupo controle e o grupo experimental apresentou-se uma diferença significativa na concentração plasmática de magnésio (P=0,005). Sendo comparados os valores da concentração plasmática de magnésio no grupo experimental antes e após a competição apresentaram-se também uma diferença significativa (P=0,005), com uma redução média de 35,23%.. Na comparação de valores pós-competição entre o grupo experimental e controle houve uma diferença significativa na concentração plasmática de magnésio, podendo assim inferir que o exercício de longa duração causa uma depledação das reservas de magnésio do organismo.
Palavras-chaves: triathlon meio-ironman; endurance; magnésio; eletrólitos
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Behavior of the ion Magnesium in triathlon half-ironman competition
ABSTRACT
The present study it had as objective to analyze the response of the ion magnesium before and after-competition of triathlon in athlete of the masculine sex, in the half-ironman distance, through it biochemistry analyzes of the concentration of the ion magnesium in the plasma blood. Ten physically active volunteers of the masculine sex participated in the present study, divided in two groups: control and experimental. The integrants of the experimental group was submitted to two blood collections (approximately 25 ml), after eight hours dietary restriction in the seated position. The second blood sample was collected immediately at ending of the competition of each athlete (t=1). For statistical analysis was used the software SPSS 11.0, and T-student test for statistical comparisons between the two groups (P<0.05 accepted as significant). When compared the values before the competition between the control group and experimental group a significant difference in the concentration of plasma magnesium (P=0,005) was observed. When compared the values of plasma magnesium concentration in the experimental group before and after competition a significant difference (P=0,005), with an average reduction of 35,23% was observed. In the comparison of values after-competition between the experimental group and control, a significant difference in the plasma magnesium concentration was detected, indicating that the exercises of long duration cause a depletion of magnesium reserves of the organism.
Key words: triathlon half-ironman; endurance; magnesium; electrolytes
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Marcos Bürger-Mendonça, Rua Paulo Barbosa 14/1102 Petrópolis, Rj, Brasil, cep: 25620-100
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