Balance Tribulus 20,000 Capsules is a high potency herbal formula, to support the stamina and endurance needed during intense physical activity or an active lifestyle. Tribulus works by maintaining the production of testosterone levels in the body. Testosterone is a naturally occurring hormone associated with muscle growth, strength and support for endurance, stamina and athletic performance. Tribulus works by maintaining the production of testosterone levels in the body. Testosterone is a naturally occurring hormone associated with: Muscle growth (anabolism) Strength Support for endurance, stamina and athletic performance.