Testosterone is an anabolic steroid and the predominate male sex hormone. It plays its primary role in the development of the reproductive organs – the testis and the prostate – in men. A secondary characteristic of testosterone is to aid in the increase of muscle and bone mass, as well as body hair growth. This hormone is vital to the overall health and well-being of men. Furthermore, it provides osteoporosis preventing benefits. Abnormalities that rise from low levels of testosterone can lead to frailness and loss of bone density.
Physiological Effects Of Testosterone In Men
Testosterone has primary and secondary sex characteristics. Androgens, via androgen receptors, promote protein synthesis. In turn, this causes the growth of tissues. These are involved in the masculinization of the male sex, development of muscle and bones and the development of sex organs.
- Supports Growth of Muscle Tissues
- Promotes Increased Strength Growth
- Increases Bone Density and Strength
- Involved in Maturation of the Bones
- Helps The Stimulation of Linear Growth
- Promotes Maturation of the Sex Organs
- Development of Erectile and Scrotal Tissue
- Causes a Deepening of the Voice in Puberty
- Growth of Facial Hair and Axillary (Underarm) Hair
Before birth, the effects of testosterone involved in the development of human children are classified into two categories. The first occurs between 4 and 6 weeks of the gestational period. This is involved in the masculinization of the neonate.
- Midline Fusion
- Phallic Urethra
- Scrotal Thinning
- Rugation (Stomach)
- Phallic Enlargement
- Gland Development (Seminal/Prostate)
In the second trimester, gender formation occurs in which androgen levels play a key role. During this period, the masculinization and feminization of behavior is influenced. This is closely influenced by the testosterone levels of the mother during gestation.
During the first week, male infants have reach pubertal levels of testosterone that eventually declines around 4 to 6 months. There doesn’t appear to be a correlation between this occurrence and bodily development. Although still mysterious, some believe this could have potential influences on masculinization of behavior.
Before puberty, the increase in androgen levels shows developmental effects on both girls and boys. During this time, adult types of changes occur.
- Development of Body Odor
- Hair and Skin Oiliness Increases
- Acne Breakout of the Skin
- Pubarche (Growth of Pubic Hair)
- Axillary Hair (Armpit Hair)
- Physical Growth Spurts
- Accelerated Bone Maturation
- Facial Hair Development
The signs of puberty occur if and when the levels of testosterone are higher than adult females for a period of months to years. This causes significant changes to boys as they grow into adult hood.
- Spermatogenic Tissue Growth
- Development Male fertility
- Enlargement of the Penis
- Increase in Male Libido
- Increased Erection Frequency
- Remodeled Facial Bone Contours
- Completion of Bone Maturation
- Adam’s Apple Growth & Voice Deepening
- Expansion of Pubic Hair Growth Areas
- Facial Hair (Mustache, Side Burns, Beard)
- Increase in Muscle and Strength Growth
In adult hood, testosterone levels continue to provide masculine traits in men. Its effects are noticeably different when in comparison to women. The levels and traits of testosterone may decline over time. The full understanding of its age related decline effects are still not fully known. Speculations include decreased libido and erectile performance.