Unfortunately, as men age, their testosterone levels start to decline which can cause a loss in bone density, decrease in muscle mass, and contribute to a higher likelihood of both metabolic syndrome and cardiovascular disease (1). Bodybuilding.com Signature Testosterone Booster contains 600mg of KSM-66 Ashwagandha and 600mg of fenugreek to help you support your body’s natural testosterone levels against these issues.

Signature Test Booster

Ashwagandha root (withania somnifera) is used in ayurvedic medicine to help various bodily functions. A 2013 study found that KSM-66 Ashwagandha supplementation increased testosterone by 17%, semen volume by 53%, sperm concentration by 167%, luteinizing hormone by 34% and sperm motility by 57% (2). In another study, Ashwagandha was shown to be able to increase exercise performance in velocity, power, and VO2 max (3).

Fenugreek is a plant native to India and North Africa which is used globally as an herb, food, spice, and traditional medicine (4). Scientists hypothesize that fenugreek contains compounds called furostanolic saponins, which help increase testosterone production. A 2017 study involving 50 men ages 35 to 65 found that taking 500mg of fenugreek led to an increase in free testosterone levels from 46% to 90% and improvements in sperm count for 85.4% of the participants (5). In another study, Fenugreek supplementation led to significant increases in strength and body composition in comparison to placebo in a double blind controlled trial (6).


  1. https://www.tandfonline.com/doi/full/10.3109/13685538.2015.1052392

  2. https://pubmed.ncbi.nlm.nih.gov/24371462/

  3. https://www.researchgate.net/publication/49694806EffectsofWithaniaSomniferaAshwagandhaandTerminaliaArjunaArjunaonphysicalperformanceandcardiorespiratoryenduranceinhealthyyoung_adults

  4. https://pubmed.ncbi.nlm.nih.gov/28266134/

  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5278660/

  6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2978122/