Dual-Action Boost Testosterone for Performance and Vitality Increase Thermogenic Action Dietary Supplement Quality Tested Pass Guaranteed Testosterone is a male sex hormone that plays a key role maintaining masculine characteristics. As a man ages, his testosterone production declines resulting in changes in cognitive function, sex drive, muscle mass, strength, and power. Furthermore, changes in metabolism make it difficult for aging men to maintain youthful body composition. Testosterone-Extra Fat Burner is a dual-pronged formula designed to boost testosterone while also helping the body burn fat by increasing metabolism and thermogenesis.