- Increase testosterone - Promote muscle recovery - Optimize sleep quality Are you seeking better sleep patterns and increased strength all in one supplement? Look no further, here at Believe Supplements we have formulated the perfect ZMA supplement for you. ZMA is a supplement that is made up of two mineral & one vitamin ingredients: Zinc & Magnesium, and B6. This supplement is supported by numerous clinical studies for assisting in testosterone production, increasing size & strength and finally improving muscle recovery.