Effects Of Long-term Creatine Monohydrate Supplementation On Anaerobic Performance Of Trained Young Adults [efeitos Da Suplementação Prolongada De Creatina Mono-hidratada Sobre O Desempenho Anaeróbio De Adultos Jovens Treinados]

The objective of the present study was to investigate the impact of eight weeks of creatine monohydrate (Crm) supplementation on the anaerobic performance of young trained adults. Twenty-six healthy male physical education students were randomly divided in creatine group (CrG, n = 13; 22.5 ± 2.7 years; 74.9 ± 6.8 kg; 178.5 ± 4.8 cm) and placebo group (PlG, n = 13; 22.9 ± 3.2 years; 71.9 ± 11.3 kg; 178.6 ± 4.0 cm). The subjects received in a double-blind system a Crm or placebo-maltodextrin dose (20 g.d-1 for 5 days and 3 g.d-1 for 51 subsequent days). Both groups had their eating habits and levels of physical fitness previously controlled. The Wingate anaerobic test (WT) was used to evaluate the anaerobic performance before and after the ingestion period of Crm or placebo. The performance indexes assessed were: relative peak power (RPP), relative mean power (RMP), relative total work (RTW) and index of fatigue (IF). ANOVA followed by Tukey post hoc test were used when P<0.05 for statistical treatment. No significant difference in RPP, RMP, RTW or IF was observed after the period of supplementation of Crm (P>0.05). The results of the present study suggest that Crm supplementation does not seem to be an efficient ergogenic resource in high-intensity and short-duration efforts involving a single set.163186190Mesa, J.L., Ruiz, J.R., Gonzalez-Gross, M.M., Gutierrez-Sainz, A., Garzon, M.J.C., Oral creatine supplementation and skeletal muscle metabolism in physical exercise (2002) Sports Med, 32, pp. 903-944Branch, J.D., Effect of creatine supplementation on body composition and performance: A meta-analysis (2003) Int J Sport Nutr Exerc Metab, 13, pp. 198-226Persky, A.M., Rawson, E.S., Safety of creatine supplementation (2007) Subcell Biochem, 46, pp. 275-289Brudnak, M.A., Creatine: Are the benefits worth the risk? 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Spectral Analysis Of Electromyographic Signal In Supramaximal Effort In Cycle Ergometer Using Fourier And Wavelet Transforms: A Comparative Study

Objective. The objective of this study was to compare these methods Fourier (STFT) and Wavelet (WT) transforms to assess muscle fatigue during supramaximal exercise. Methods. Twenty five subjects of both genders (13 men, age = 28.2 ± 2.7 years and 12 women, age = 23.2 ± 2.7 years) performed the Wingate test, during which the electromyographic responses of the superficial muscles of the quadriceps were examined. For analysis we used the STFT and WT transforms, which provided the following variables: median frequency (MF), slope and variance. Results. The results showed no differences (P > 0.05) in MF and slope. However, there were differences for the variance between the analysis (P < 0.05). Conclusion. 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