As long as there have been sports, there have been athletes in search of an advantage. And of all of the ways to get a leg up, these days professionals often turn to performance enhancing drugs. You hear about them in just about every sport. In the US some of the best baseball players of all time have been accused of using PEDs, American football players are regularly suspended for failing drug tests, and of course Lance Armstrong famously finally came clean about blood doping in 2012, vacating his seven Tour de France victories in the process. And then there's the whole deer-antler-spray-thing.

There's no shortage of ways athletes try to enhance their performance. Some of them work, but at high cost to their health or wealth, and others just don't work at all. So, which are which, and how do they work and not work? Give me a few minutes and I'll give you a few lessons in the science of why cheaters never win.

(Intro)

We refer to them as 'drugs', but most performance-enhancers are versions of the chemicals that you already have in your body. These are the compounds that your body uses to build and heal itself and keep itself healthy, but by ramping up the levels of these compounds, in the hopes of getting more out of your body, you could end up putting yourself in a world of hurt.

HGH, or Human Growth Hormone, is a good place to start. Even though we all have it, a lot of people have no idea what it is.

Your body produces HGH from the pituitary gland at the base of your brain. It stimulates growth and cell development, and it works with another hormone called Insulin-like Growth Factor One, also known as IGF-1. HGH is converted into IGF-1 in the liver and it has several effects throughout the body, including increasing bone and muscle growth.

A natural production of HGH peaks during your teenage years, starts to steadily decrease by the time you hit thirty, and declines through the rest of your life. Growth hormone does help regulate metabolism in adults, but its main purpose is really to spur growth during childhood. Since 1985 an injectable form of HGH has been produced synthetically and the US Food and Drug Administration approved it to treat children with growth issues, genetic disorders, and kidney problems. For adults HGH might be prescribed for conditions like bone loss or high cholesterol or very rare pituitary tumors.

Despite its high costs -a month supply of HGH can cost up to five thousand dollars- Human Growth Hormone has become popular among athletes looking for an edge. A big reason for this is that it is really hard to detect, since everyone's body produces it. Also HGH starts to break down within thirty minutes of injection, so even the best tests can only detect it, like through abnormally high levels of certain antibodies in the blood, within twelve to twenty four hours.

But here's the thing: for all the athletes and dozens of sports who take HGH there's actually very little evidence that it provides any performance enhancement. HGH may stimulate muscle and bone growth, but whether that translates into increased power or strength or endurance is unclear. Researchers in California recently conducted a review of forty four studies of growth hormone in athletes. More than three hundred volunteers, in all these studies combined, received injections of growth hormone for an average of twenty days, similar to a drug cycle that an elite athlete might use. While those who received the HGH instead of the placebo did increase their lean body mass by over two kilograms, there was no measurable increase in either their strength or their exercise capacity. There's been all of one study that reported a positive effect of growth hormone on athletic performance. At the University of Queensland in Australia scientists in 2010 studied a hundred and three recreational athletes and found that while those taking HGH showed no improvement in strength of general fitness, their sprinting times on a bicycle improved by four percent. That's all. Not a huge difference. But in a competitive event four percent could represent the difference between winning the gold and finishing last.

What several of the other studies did find, and what anti-doping agencies have discovered, is that the performance does improve when HGH is used with testosterone. And do you know what they call synthetic derivatives of the hormone testosterone? If you said 'anabolic steroids' then you win a gold medal of your own.

We've talked about steroids before, but it's kind of impossible to talk about performance enhancers without touching on them again.

Steroids are a kind of lipid, or fat, molecule that your body makes two very different types. One type that you might be familiar with are corticosteroids. They're hormones produced by your adrenal glands down there on your kidneys and they're handy at things like immune function stress response and controlling inflammation. You may have been prescribed medications that are synthetic versions of these steroids to treat joint injuries or an auto-immune disease or just really bad poison ivy rash, which is why I took it.

The other kind of steroids are androgenic-anabolic steroids. The main one of these is testosterone, which as you know produces male sex characteristics, but these steroids also include compounds that stimulate the synthesis of proteins and, eventually, new muscle fibers. This process is called 'anabolism', and the steroids that drive it are anabolic steroids. The synthetic versions of these bad boys are used illegally by athletes - actually 'abused' might be the better term here. The combination of steroids and exercise can increase a man's strength by more than thirty eight percent, and it's at least that high for women. Anabolic steroids can be freakishly efficient, especially when the user takes more than one. Doping athletes generally take steroids in cycles lasting between one and three months, when strength training in the off-season. This is also when they're less likely to get tested.

When injected or swallowed these steroids travel to muscle tissue, where they attach to receptors on the membranes of muscle cells. The receptors deliver the steroid hormones to the nucleus of the cells where they stimulate anabolism: the synthesis of proteins.

But anabolic steroids also carry with them some crazy side effects. Not only do raised testosterone levels often lead to increased aggression and sex drive, but they can also, strangely enough, lead to shrinking testicles, impotence, and heart damage. In women steroids can cause facial hair growth, acne, liver damage, breast reduction, and changes to or total stopping of the menstrual cycle. Not that you were wondering but I can assure you that this body is completely steroid-free. I mean, do I have to list the side effects again? Don't do that.

Also, if you're more into aerobic activities, especially competitive bicycle racing, can I suggest that you not partake in blood doping? Bicyclist and other endurance athletes will often use anabolic steroids, but blood doping is becoming more and more common, in large part because it's harder to detect.

This kind of doping generally works in one of two ways: either through direct blood transfusions -in many cases athletes use their own blood- or through injections of a synthetic form of erythropoietin or EPO, a hormone that controls you body's production of red blood cells. In both cases the goal is the same: to increase the number of red blood cells in the body to increase physical stamina.

Red blood cells use a protein called hemoglobin to bind with oxygen and deliver it throughout your body. Since your body uses up to twenty percent more oxygen during strenuous exercise than while resting, if you can raise your red blood cell count by having more blood, or with EPO, your tissues can keep getting the oxygen they need. Then you can keep cycling or whatever for a lot longer, and before you know it you've won the world's most famous bicycle race! By cheating!

The dangerous world of PEDs is of course not limited to HGH, steroids, and blood doping. The longer you look, the stranger the stories you will hear of athletes attempting to get an edge. This includes baseball player Manny Ramirez who, in 2009, was suspended for fifty games after testing positive for Human Chorionic Gonadotropin, a hormone that women produce during pregnancy. Turns out it also boosts testosterone levels in men and can increase sperm production. Ironically, many steroid users take HCG after developing fertility problems.

PEDs also aren't limited to sports where the competitors aim to be stronger or faster. In 2008 a member of the North Korean Olympic team was stripped of two medals after testing positive for propranolol. Propranolol is a drug used to treat hypertension and prevent trembling. The sport in question: shooting. Similarly PED use is also a problem in the archery world, where shaky hands can lead to poor performance.

And then there is deer antler spray, a PED that you probably didn't know existed until 2012. That's when NFL player Ray Lewis admitted to using the stuff in the hopes of speeding his recovery after tearing a bicep. The velvety tissue on young deer antlers contains high levels of growth hormone IGF-1 that I mentioned earlier. This is partly what makes antlers grow so quickly. Some companies claim that they can extract this hormone from the tissue and then put it in a spray that can be administered under the tongue.

You will no doubt be shocked to hear that there's no evidence that IGF-1 can be successfully delivered in a pill or spray form, even if the hormones comes from the antlers of some super deer in New Zealand. And yet deer antler spray has fast become one of the more popular supplements on the market.

So here's my advice to all the athletes out there: if the choice is between injecting yourself with synthetic testosterone that makes you sterile and unable to have sex, changing the amount of blood you have in your body, or buying some crazy concoction supposedly made from a deer's head and putting it under your tongue, I recommend choosing none of the above.

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