Dados do Trabalho

Título

Relationship of acute melatonin and caffeine intake on performance and sleep-wake rhythm parameters of street runners

Introdução

In recent years there has been a significant growth in the practice of street racing, originated by several interests, such as health promotion, aesthetics, social integration, escape from stress and pursuit of pleasurable and competitive activities.Sports nutrition, through the usage of ergogenic substances, has emerged as an important tool to increase energy demand, as well as the rate of energy production for muscle and muscle tissue growth, favoring athletes; sports performance. Caffeine is a substance that has been considered a nutritional ergogenic supplement for being present in many drinks consumed daily and its use has become quite common in sports, especially in recent years, particularly by athletes competing for endurance events. As well as caffeine, melatonin has been tested as a potent nutritional ergogenic supplement, but its effects are not yet fully understood. Sleep can be a determining factor for the high athletic performance. The intensity of physical exercise is known to be directly related to the sleep pattern. And both melatonin and caffeine can positively or negatively affect sleep quality as well as sports performance.

Objetivo

This study aims to evaluate the relationship of acute melatonin and caffeine supplementation on sleep-wake rhythm performance and parameters in street runners.

Métodos

Twenty-four male street runners will undergo three 1,600-meter physical tests. To monitor the sleep-wake rhythm, athletes will use the actigraph for 6 days (3 days before and 3 days after each physical test). The study will be double- blind and randomized, and at each session participants will eat 40 minutes before the 1600m test, a caffeine capsule (5 mg / kg), melatonin (5 mg) or placebo (5 mg). After the test, for 5 hours, the effort (Borg scale) and drowsiness (Karolinska Questionnaire) questionnaires will be applied to assess subjective perception. In addition, the Chronotype (Horne & Ostberg) and Pittsburgh questionnaires will be applied at the beginning of the study, along with the signature of the informed consent form.

Resultados

No results

Conclusões

Ingestion with melatonin and exogenous caffeine is expected to have significant ergogenic effect for participants undergoing the proposed 1,600-meter running exercise model.

Palavras-chave

Performance, melatonin, caffeine, street runners and sleep-wake cycle