Effect of acute medium-chain triglycerides (mct) supplementation on time to exhaustion in swimming trained rats

Author(s)

Michel Dacar

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola de Educação Física e Esportes (EEFE/BT)
• Defense date: 2000-11-13

Examining board members

Antonio Herbert Lancha Junior; Eduardo Kokubun; Marinilce Fagundes dos Santos

• Advisor: Antonio Herbert Lancha Junior

Abstract

The fatigue processes during exercise can be of peripheral and/or central origin. The peripheral fatigue mechanisms are related to exercised muscles and can occur by protons accumulation, ATP/CP and muscular glycogen depletion. This last factor is one of the most important determinants of the onset of peripheral fatigue during moderate to high intensity long lasting exercises. Central fatigue is related to central nervous system (CNS) and can occur by low glucose concentration (hypoglycemia) and probably by high 5-hydroxytryptamine (serotonin) concentration in certain areas of CNS. Many authors proposed that some nutritional supplements are able to modulate, on a positive way, metabolic processes of organs and tissues involved with exercise, sparing endogenous energetic substrates (muscular and hepatic glycogen) and/or altering specific neurotransmitter synthesis (serotonin). The aim of this study was to analyze the acute medium-chain triglycerides supplementation (1 ml) on time to exhaustion in swimming trained rats during 6 weeks, 5 days a week, submitted to moderate (5% of body weight attached to the animal chest) or intense exercise (the percentage of extra-weight used in this group was equivalent to the metabolic anaerobic threshold). The results showed that MCT supplementation was efficient to increase effort tolerance in animais submitted to moderate exercise, the same was not observed when the animais swan to exhaustion above the metabolic anaerobic threshold (AU)