What is a performance enhancing drug? Where do we draw the line between health drinks and illegal substance? There are many substances banned by the Olympics and other sporting organization, and while they all artificially enhance performance they don't all do the same thing.
There are a number of different types and they work by different mechanisms. Lets go through the main players. The scientific name for all of these drugs is Ergogenic Aids (meaning "energy giving" medications).
ANABOLIC-ANDROGENIC STEROIDS.
These are your classic "roids" that weight lifters take to get them jacked up. What does anabolic mean? Anabolism is when your body holds onto nitrogen to increase protein production (proteins are essential for muscle creation). This anabolic state is achieved through the Androgen Pathway...which is activated by testosterone. Therefore Anabolic-Androgenic Steroids (AAS) are synthetic (meaning created in a laboratory) derivatives of Testosterone.
The average male produces about 7 mg of testosterone (from the testes) every day. But as we get older our production declines, and an 80 year old male produces only half of a 20 year old. Significant increases in muscle growth and strength occur when people take doses of > 300 mg every week (compared to about 50 mg naturally made each week in men).
Testosterone plays a role in promoting muscle mass (anabolic state... growth, versus catabolic state, wasting away, which you see in people with cancer). Specifically testosterone (and the anabolic steroids) promote lean body mass, hypertrophy (overgrowth) of muscle fibers, and subsequent increase in muscle strength. Steroids also improve muscle exercise tolerance, protect muscle fiber damage from overload forces, and increase the rate of protein synthesis during recovery phase. It also increases collagen production and bone density. Testosterone and AAS not only affect the skeletal muscles but also act on the brain causing euphoria (happiness), increased sexual drive, aggression, energy level, and thus promotes exercise.
One example of a steroid used, is Androstenedione which Mark McGwire admitted to consuming, which is an androgen produced by the testes. Its a precursor to testosterone.
While these drugs have attracted a lot of attention with Major League Baseball, the Olympics etc, the vast majority (over 66%) are used for cosmetic reasons in non-competitive athletes. Over 3 million americans have used anabolic steroids, while about 3% of the male population has used steroids (thats around 20 million people). Multiple AAS medications are usually "stacked" and taken in cycles lasting 4 to 12 weeks giving mega-doses of synthetic testosterone, followed by a "clearance phase" of 1 month where no medication is taken, to prevent major medical complications from developing. Yet roughly 90% experience at least one minor side effect including acne (50%), testicular atrophy (40%), stretch marks (40%), and pain at the injection side (30%). Many steroid users experience tendon ruptures, and while steroids themselves appear to alter the structure somewhat of the tendons, they do not appear to significantly change the strength of the tendon, which suggests that these tendon ruptures simply occur because of the large increases in weights being lifted and the tendon is the "weakest link of the chain". There have been case reports and other medical publications associating steroid use with more significant medical conditions such as heart arrhythmias, hypertension, promotion of certain cancers, liver damage, and increased mortality rate (4.5x higher in chronic steroid users than the normal population).
GROWTH HORMONE.
Naturally produced by the body's pituitary gland, which hangs off the brain like a little sack. Growth Hormone promotes an anabolic state (protein production), similar to testosterone (in fact, testosterone activates the pituitary gland to produce GH). The problem with growth hormone is that it not only makes muscles bigger, but it makes everything bigger, including your facial bones (this is what causes a big head in baseball players taking steroids, or the large mouth and gap between teeth in weight lifters taking steroids), and it makes your heart bigger which sounds great except that your heart tires out more easily when its huge because it doesn't pump blood as efficiently and this leads to heart failure.
Oxygen Enhancers
Red blood cells carry oxygen to your muscles, which allow your muscles to contract (think of oxygen as the spark that starts a combustion reaction, therefore, the more sparking in your muscles, the greater the power). Therefore many athletes, especially endurance athletes look for ways to increase oxygen in their blood. This is achieved in a number of ways.
* Blood Doping
This was a technique used by many cyclists. They essentially were giving themselves blood transfusions just before races to increase the total number of red blood cells circulating in their body to improve oxygen carrying of their blood.
* r-EPO (recombinant erythropoietin).
Erythropoietin is a natural hormone found in the body that tells your bone marrow to produce more red blood cells. r-EPO is just a synthetic version. It increases the red blood cell production in the body, and therefore allows more oxygen to be carried in the blood and thus allows more muscle contractions without the muscles getting tired.
* Meldonium
This is the medication that Maria Sharapova was caught taking and caused her ban from professional women's tennis. This medication was initially developed for patients with clogged arteries. The medication dilates blood vessels to improve oxygen delivery to the muscles (including the heart).
MENTAL AIDS: First olympics in greece 776 BC documented athletes using sesame seeds (probably for opioid effects) and hallucinogenic mushrooms.
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