What is Winstrol (Stanozolol)?
Stanozolol refers to a synthetic anabolic steroid that is derived from testosterone. Testosterone is a male sex hormone that is responsible for the male sexual characteristics and the muscle structure. 
Anabolic steroids such as winstrol are commonly used by bodybuilders to build the lean muscles in their body and burn the excess fat.
Stanozolol is generally prescribed to treat a condition known as hereditary angioedema which is characterised by occasionally recurring swelling in different parts of the body. This condition occurs due to increased water retention in the body of the affected individuals. It has also been used to treat anaemia, a disorder characterised by decreased red blood cells in the body. Stanozolol has been used as treatment for various other medical conditions such as vascular disorders and growth failure as well. 
What Is the Effect of Winstrol on the Body?
Winstrol reduces the frequency of swelling in individuals suffering from hereditary angioedema. Winstrol prevents the retention of water in the body and thereby decreases the symptoms of hereditary angioedema. It has also been noted to increase the red blood cell production in the body.
In case of animal studies it has been noted that winstrol improves muscle growth, increases bone density, improves the production of red blood cells and also stimulates the appetite.
How Does Winstrol Help in Fat Loss?
Winstrol is used by bodybuilders and athletes to lose fat and retain lean body mass. The ability of winstrol to avoid water retention may be beneficial in this regard. Some amount of the hormone testosterone is able to get converted into oestrogen and thereby can result in water retention. However, the amount of testosterone in winstrol is considered to be quite minimal and does not produce such effects.
It has also been believed that winstrol has a diuretic effect; it improves the excretion of water from the body. Further winstrol may have fat burning abilities. It promotes faster utilization of fat cells in the body and induces an overall reduction in fat mass in the body. Winstrol is believed to increase strength without an increase in body weight. Hence it is a favorite drug among bodybuilders and other sports persons who aim to gain muscle mass and strength without an increase in the fat content in the body. 
How is Winstrol Used?
Winstrol is commonly used by bodybuilders in a cutting cycle to preserve the lean muscle mass while increasing the utilisation of fat tissues. The aim of such cutting cycles is not to increase the bulk of the muscle mass but to preserve the lean mass and reduce the fat content in the body. Although the fat burning abilities are not completely proven, winstrol is generally used for this property.
Winstrol injections or oral tablets used in cutting cycles increase the amount of free testosterone levels in the body. Thereby, it helps the body to utilise larger amounts of testosterone for preserving lean muscle mass and burn the excess fat tissues. It has also been noted that winstrol does not result in weight gain when used in cutting cycles. Other anabolic steroids are used in the bulking cycle wherein their main aim is to build up muscle mass.
How Is Winstrol Abused in Sports and Bodybuilding?
The FDA has approved the synthetic anabolic steroid stanozolol (winstrol) for use in humans for medical reasons only. Any other use of stanozolol is banned in the United States. Winstrol has commonly been abused by individuals involved in bodybuilding and other sports. Bodybuilders mainly use winstrol in cutting cycles to preserve lean muscle mass and increase the utilisation of fat tissues. It is also preferred as it does not increase the weight on regular use.
Furthermore, it has also been believed that the use of winstrol is not associated with the other anabolic effects of testosterone such as increase in breast size in case of males and initiation of male characteristics (such as change in voice pattern and hair loss) in females. This makes winstrol a popular drug among athletes, especially female athletes, as most of the other anabolic steroids result in such adverse effects. Furthermore, it has also been noted to be used by athletes involved in fast sports such as track and field events which require a combination of strength and speed.
Winstrol is believed to result in the development of lean muscles without the retention of fat and water in the body. The use of winstrol by sports persons has been banned by sporting authorities and many athletes have been stripped off their medals after being tested positive for the use of winstrol, including Ben Johnson’s victory in the Seoul Olympics 100 metres final and his subsequent disqualification for doping.
In 2010, Stanozolol was withdrawn from the US market and it was classified as a Schedule III controlled substance under federal regulation, the Anabolic Steroid Control Act of 2004 and the updated Designer Anabolic Steroid Control Act of 2014. 
Why Is Winstrol Popular Among Women?
Anabolic steroids are commonly associated with increased androgenic effects in women on regular use. While some of these effects may be reversible on discontinuation of the use of anabolic steroids, many changes are irreversible and hence are not preferred by many women. Winstrol does not have this property, making it quite popular among female athletes.
Winstrol is believed to provide the anabolic (muscle building) effects with very minimal androgenic effects. Thereby the androgenic effects such as deepening of the voice and male pattern loss of hair is rarely observed with the use of winstrol in women. Additionally, the ability of winstrol to reduce fat and increase the lean look also makes it a most preferred choice of anabolic steroid among women involved in bodybuilding and other sports.
However, reliable sources report that side effects of stanozolol include those commonly associated with anabolic steroids such as :
- Menstrual irregularities, acne, atrophy of the breasts in women, and impotence,
- Testicular atrophy, prostatic hypertrophy in men.
- The risk of heart attacks, strokes, liver damage, and psychiatric disturbances could occur in both sexes.
What Are the Side Effects of Winstrol?
The abuse or over-use of winstrol for prolonged duration has been associated with several side effects. Most abusers generally consume winstrol in quite high quantities when compared to those approved for regular use. Liver toxicity has been noted to be the most common adverse effect of prolonged use of winstrol. Other side effects include pain in the joints, increased development of breast tissues in men, and water retention.
Winstrol is contraindicated in individuals suffering from different disorders such as prostate cancer, breast cancer and hypercalcemia (a condition characterised by high levels of calcium in the blood). A healthcare provider has to be consulted if one has a history of heart attacks, high cholesterol levels, and diabetes or is consuming medications for any other associated conditions.