At a certain age, men's bodies start to undergo specific changes related to aging. The body's metabolism slows down, sex drive can decrease, and the vim and vigor a man once was accustomed to feeling can appear only occasionally, or not at all. When these changes occur later in a man's life, they can be natural signs of aging. Men who are elderly don't have the same energy levels or body types as younger men. So it's normal for these changes to occur. But for men who are not yet elderly, t...

Testosterone is something everybody has in varying levels. Although it is known as the male sex hormone, it is present in women's bodies as well, although in much lower levels than men. Testosterone is produced primarily in the testicles in men, and in the ovaries and adrenal glands in women.and plays a key role in the development of male growth and the development of male characteristics, such as men's deeper voices and sex drive. It also is essential in the creation of muscle mass and stron...