ZMA (Zinc monomethionine aspartate and magnesium aspartate) supplement is used during training for increased muscle strength. In the initial studies by Dr.Brille and Conti (Victor conti was the developer of the supplement), it was found to significantly increase zinc , magnesium and free serum testosterone levels in persons taking ZMA compared to others.
Further studies in 2004 and 2006 contradicted these results as they found no increase in free or total serum testosterone levels. However both studies noticed increase in zinc levels in people taking ZMA supplements.
Testosterone plays key role in sperm production. Zinc is an important trace element required for many enzymes in our body. It is rich in semen and also plays a role in spermatogenesis and testicular function. There is no evidence that ZMA increases sperm count as of now. But, if at all it should increase sperm count, it has to be due to increased zinc level in the body but not due to testosterone increase as evidenced from studies.
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