The effects of ethanolic extract of the leaves of Erythroxylum mucronatum (Benth.) (Erythroxylaceae) on strength and muscle performance of resistance trained rats

Background: The Erythroxylaceae family is known worldwide for its species that contain compounds with a marked positive effect on physical performance, such as ephedrine and coca. E. mucronatum is a species of this family found in several parts of South America, mainly in the northern and northeastern regions of Brazil, used by natives to improve strength and physical performance. Purpose: We set out to investigate, for the first time, in a series of experiments whether the ethanolic extract of E. mucronatum (EEM) had any effect on performance and strength of rats undergoing resistance training. Methods: We promoted a supplementation with EEM and searched it increased strength, muscular endurance and reduced body fat in the rodents. Results: we registered a significant reduction in lipid peroxidation and an increase in superoxide dismutase in the exercised muscles. EEM supplementation did not alter the effect of exercise on blood pressure and heart rate. Additionally, we noticed a significant reduction in two markers of muscle damage, CK and LDH, but no alterations were observed in the levels of ALT and AST. Conclusions: The results showed that EEM was able to improve the physical performance of the rats without any remarkable adverse effects on hemodynamic variables, so it should be further investigated to examine whether it also has potential as an effective dietary supplement in humans to improve performance in resistance exercise cycles.