Anabolic

These are typically the desired effects, and although the greatest effects are seen in females and hypogonadal or castrated males, some gains can be seen in physiologically normal males. Anabolic steroids have been shown to increase weight gain, fat-free weight gain and muscle fiber area in conjuction with a strength training program. Strength gain, as measured by one-repetition-maximum tests can also be increased by steroid use. These effects are often difficult to attribute solely to action of the steroid itself, as the euphoria associated with their use can encourage more rigorous workouts.

Steroids administered to previously untrained men beginning a weight training program appear to provide no benefit. It is only when highly trained individuals add a steroid regimen to their existing program that training gains are enhanced.

Androgenic

These are generally considered undesirable or side-effects and can be permanent and quite serious. The additional metabolic load on the liver can lead to dysfunction (including peliosis hepatis and hepatoma). This appears to be particularly true of the methylated (generally oral) derivatives. Increased levels of circulating testosterone analogs can act as negative feedback to the pituitary gland, decreasing spermatogenesis and production of natural testosterone and luteinizing hormone. Decreases in circulating HDL (beneficial lipoproteins) and increases in LDL (harmful) levels have been reported.

A number of behavioral changes are also associated with steroid use. Irritability, increased aggressiveness, nervous tension accompany the euphoria and reduction in fatigue noted by up to 80% of steroid users.

The masculinization of women using steroids is well accepted. Typical observations include hoarsening of the voice, hirstism, an enlarged clitoris and decreased breast size.