Actualy the Siberian Ginseng doesn't increase testasterone the way that Red Korean or Chinese Ginseng will. I think of Siberian more more physical endurance, brain stimulation etc.

The Red Ginsengs are more for blood tonic, healing, testasterone production, etc. Siberian is so different from the other Ginsengs it's often arguable why it even shares the name.

I've used quite a bit of both in my life - so this is from experience.

I see ginseng more as a generally stimulating agent, it probably doesn't have specific hormonal effect. But I am open to new data.