In combination with the sport and a healthy diet food I get remarkable and encouraging results! Exit the urban legend that wants the presence of soy protein contain enough feminizing hormones (phytoestrogens) neutralizing our testosterone and therefore Mammut Protein scared. I can testify that I have stayed a man more muscular than before, any sexual disorder, and moreover there should be more wary of stressors, sleep, alcohol, tobacco, heat, pollution them, are actually factually down testosterone levels and fertility. Excellent quality / price 37EUR / 3kg or about 12.5 eur / kg with a good dosage of arginine and glutamic acid! I highly recommend!