To ensure a steady progress in bodybuilding, it is important to put the odds on your side. An optimal production of testosterone is a key element of building muscles. Neo Slim 550 You can exercise so hard during your workouts and eat many protein supplements: If your testosterone rate is low, your muscle growth will be very slow. To give you an example, women produce 10 times less testosterone than men: this explains their lower potential for muscle hypertrophy.