Unlike most, Six Star Testosterone Booster delivers a key ingredient shown in a human clinical study to amplify your body’s natural testosterone production within the normal range. It even delivers a blend of ingredients shown to improve athletic performance. BOOST ACTIVE (FREE) TESTOSTERONE 1Six Star Testosterone Booster is formulated with a precise dose of the mineral boron, which is shown in human clinical research to increase active (free) testosterone in just 7 days. MAINTAIN PEAK TESTOSTERONE TO CORTISOL RATIO 2Six Star Testosterone Booster is also scientifically engineered with a unique, plant-based blend shown in a 7-week human clinical study to help maintain peak testosterone to cortisol ratio after an intense training regimen. Cortisol is a hormone released due to stress that can break down muscle tissue. ENHANCE PERFORMANCE 3In the same study, test subjects also enhanced performance as determined by a marker of training capacity.