Ergogenic Effects of Yohimbine: Standardized Cycling Clinical Study


background: Ergogenic denote rising in the capacity of the body for eliminating exhaustion and enhancing physical performance, with broad variety of drugs are apparent to be ergogenic in their effects. Yohimbine is an alkaloid recognized as an antagonist to the noradrenergic α2-receptors which normalize noradrenaline release in the central nervous system and their activation decreases the discharge of noradrenaline in the synaptic terminal.Objectives: This study was designed to evaluate the ergogenic effects of yohimbine in normal healthy volunteers.Patients and Methods: The present study was conducted in Department of Pharmacology, College of Medicine, Al-Mustansiriya University, Baghdad-Iraq, in collaboration with Department of Pharmacology, College of Medicine, University of Kerbala, Kerbala-Iraq, during April of 2013. The subjects of this study were medical students. 20 male volunteers were conformist to join up this single blind random experimental study. The exercise program consists of cycling on an ergometer. Pulse was measured using ear pulse sensor and maximum pulse rate achieved in this study and the entire exercise parameters were recorded as baseline data, then each subject take yohimbine tablets 5 mg (orally) and after 2 hours, each subject run on cycling ergometer to fatigue state, then, the display functions of bicycle were scanned. Besides, maximal oxygen uptake (VO2 max) was measured to estimate oxygen consumptions.Results & discussion: Yohimbine significantly improved all ergogenic parameters (efforts, calories, distance, speed and exercise time) from baseline after single oral dose of 5mg, where p values were ˂ 0.05. Moreover; yohimbine significantly accelerate the oxygen consumption in both oxygen consumptions and velocity at maximal oxygen uptake regarding maximum heart rate and resting heart rate with p values ˂ 0.05.Conclusions: Yohimbine accelerates and improves cycling performances via positive ergogenic effects .So, yohimbine can be used as ergogenic agent for ameliorating the physical fatigue.