I will now devote two videos to the topic of performance-enhancing drugs. The widespread use of these drugs is alarming and extends from professional elite athletes down to student athletes in junior high school. The extreme competitiveness in professional sports, along with the allure of multimillion dollar contracts and endorsements, has driven many athletes to use performance-enhancing drugs to gain an edge over their competition. In this video and the next, I will discuss the most common drugs and techniques used to improve performance as well as the mechanisms whereby they can potentially exert their effect. To fully appreciate the extent and scope, as well as the complexity involved with these many banned substances and methods, I suggest you visit the website for the World Anti-Doping Agency. In the field of exercise science, the term Ergogenic Aids is used to describe any substance or technique other than normal training designed to enhance or improve performance. I will begin by discussing anabolic steroids. Athletes interested in increasing muscle strength and mass, such as football players, power lifters and bodybuilders, are the frequent abusers of this class of drugs. The use of anabolic steroids, when coupled with heavy resistance training and a high protein diet, can be very effective in accomplishing these goals. Examples of their effectiveness are shown here. These images have not been photoshopped. No matter how hard you train in the weight room or how much protein you consume, you will not get results like this unless you're using anabolic steroids. And when used properly, anabolic steroids will work for both men and women alike. Anabolic steroids are similar in structure to the hormone testosterone. Most anabolic steroids attempt to maximize the anabolic effects, or muscle-building effects, of testosterone while minimizing the androgenic effects which produce secondary male characteristics such as an increase in facial hair and a deepening of the voice. Anabolic steroids can be administered both orally or injected directly into the muscle of choice. It is common for bodybuilders to use both techniques. Here is a list of the most commonly administered oral and injectable anabolic steroids used by athletes. The practice of stacking, in which two or more different anabolic steroids are used - mixing oral and/or injectable forms - can sometimes produce added results. Additionally, the process of pyramiding is another common technique whereby the athletes gradually increase the dose and frequency of steroid use, reaching a peak amount. This is followed by a tapering period, where the dose is slowly reduced with the hope of minimizing the negative side effects associated with prolonged steroid use. Anabolic steroids act by entering the muscle cell, where they interact with their specific receptor. The hormone receptor complex then enters the nucleus of the muscle, where it can alter gene expression - exerting its effect on the production of new muscle tissue. I remind you that in order to be effective in increasing muscle mass, anabolic steroids must be coupled with heavy resistance training and a high-protein diet. The use of anabolic steroids is banned by just about every sport and detection can result in suspensions, disqualifications and permanent banishment. More importantly, the side effects associated with chronic steroid use can be quite severe - including brain and liver cancer, heart and kidney disease, depression and violent behavior. Here is just a short list of some of these harmful side effects from steroid abuse. Considering the health consequences, the use of anabolic steroids is clearly not worth the risk and should be avoided at all cost. Another drug taken by athletes to improve strength is the human growth hormone. To date, research studies indicate that the growth hormone is not nearly as effective in increasing muscle mass and strength as are anabolic steroids. Nonetheless, growth hormone abuse is common amongst many sports today and unfortunately, it's repeated use is associated with serious side effects as well. There are many other products and supplements readily available over the internet that tout their muscle building prowess - including various growth factors, amino acid supplements and even insulin-like growth factor. In general, these products have been shown to be ineffective in increasing strength, come with their specific side effects and can be very expensive as well. However, one supplement that appears to be effective in increasing strength as well as recovery from intense exercise is creatine. Supplementation with creatine will lead to an elevated concentration of creatine phosphate levels in skeletal muscle. As discussed in our video on fatigue, creatine phosphate depletion is a common cause of fatigue during short-term, high intensity bouts of exercise. Having more creatine phosphate onboard prior to a strength-training session will allow you to squeeze out a few more repetitions before fatigue sets in, thereby contributing to a greater overload stimulus and subsequent training adaptations. As a reminder, creatine phosphate is a rapid, immediate source of fuel for ATP production. Shown here are the results from one study demonstrating that when compared to subjects taking a placebo, the subjects consuming creatine has significantly greater gains in muscle mass, strength and fiber area after 12 weeks. Creatine supplementation is done in two phases; an initial loading phase with the higher doses of creatine, followed by a maintenance phase with continued consumption of lower doses. Creatine loading is also effective for athletes that have to perform repetitive, short, high-intensity exercise bouts. Having greater availability of creatine in muscle after the first intense bout of exercise will allow for a faster resynthesis and replenishment of the creatine phosphate stores prior to the second bout of exercise. This beneficial effect is shown here. When subjects were asked to perform repeated bouts of high-intensity cycling with only 30 to 60 seconds of rest between bouts, the individuals supplemented with creatine were able to accomplish more work when compared to the placebo group. In summary, when coupled with heavy-resistance training and a high-protein diet, anabolic steroids are effective in increasing muscle mass and strength. The serious health consequences and the unethical nature for competition are reasons to avoid their use. Many of the other supplements purported to increase muscle mass and strength are likely ineffective. Creatine supplementation can lead to improvements in strength as well as a faster recovery from repeated bouts of short-term, high-intensity exercise.