Testosterone is the main anabolic hormone and is well known to promote gains in muscle size when elevated in the blood. However, it is less clear how testosterone levels are related to muscle strength and power. To address this question, researchers obtained a resting blood sample in 70 elite athletes from a variety of sports and compared testosterone levels to explosive performance as measured during a countermovement vertical jump. When the testosterone and jumping performance measures were compared, it was discovered that a relationship existed. Individuals with higher testosterone levels were the ones who had the highest explosive power and those with lower testosterone had lower performance output. This close relationship between testosterone and performance supports the idea that testosterone is an important determinant of neuromuscular function. The findings suggest that increasing testosterone naturally
may benefit not only gains in muscle size, but also muscle function.
Cardinale M, Stone MH. Is Testosterone Influencing Explosive Performance? J Strength Cond Res. 2006 Feb;20(1):103-107.