Tribulus Terrestris is a herb, which contains substances, in different concentration, called steroid saponins. The active steroid saponin, to which are due the anabolic qualities of this herb is the substance protodioscin. The protodioscin stimulates the secretion of luteinizing hormone from the hypophysis. In the male organism the luteinizing hormone increases the testosterone levels as it stimulates the secretion of free testosterone in the testicles. The male sex hormone testosterone has strongly expressed anabolic activity. Its higher levels significantly stimulate muscle growth, increase muscle power and endurance. In the female organism the luteinizing hormone increases the levels of female sex hormones and this is the reason why the intake of Tribulus Terrestris from females does not lead to anabolic effect. Hence, its intake is inappropriate for females who want to increase muscle growth, power and endurance. Tribulus terrestris’ intake is recommended for male who want to increase muscle mass, power and endurance. Its combination with the food supplement Ecdysterone increases significantly its anabolic effect, similar to some light synthetic anabolic steroids, but without their side effects.