CSCS Study Guide Chapter 11: Performance-Enhancing Substances and Methods

Chapter 11 of the Essentials of Strength Training and Conditioning covers performance-enhancing substances and other methodologies. It is the job of the Strength and Conditioning professional to be aware of their governing organizations banned substance lists.

This chapter is about performance enhancement using substances, including anabolic steroids. The needs of athletes are different and reflect both health but, mainly sports performance goals.

There is discussion of what to eat before, during and after training as well as a little information on eating disorders.

Performance-Enhancing Substances and Methods

  • There are a number of substances that athletes take in hopes of enhancing their performance. Governing sport bodies have lists of which things are permissible and which are not.
  • It is important to stay up on whether research supports substances and their claims for safety, legality and just to know if they actually work.
  • Ergogenic Aid - any substance, mechanical aid, or training method that helps improve sport performance. This chapter is mainly concerned with the substances.
  • Athletes should focus on good nutrition and solid training principles. Once these two have been addressed, nutritional supplements and ergogenic aids can be considered.

Types of Performance-Enhancing Substances

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  • Testosterone - the primary male sex hormone that interacts with skeletal muscle. An androgen, natural or synthetic compound.
  • Anabolic Steroids - human made derivatives of testosterone. Also referred to as anabolic-androgenic steroids, androgens or androgenic steroids.
  • "Stacking" - taking several different drugs at the same time. Rationale for doing this is to increase the effect of each drug with an additive effect. Research in this area is limited.
  • People and athletes outside of sport use anabolic steroids for reasons that range from appearance to athletic performance.
  • Muscle Dysmorphia - also known as reverse anorexia nervosa, the belief that one who is very muscular, is not.
  • An increase in lean muscle mass and decrease in fat mass may last for several months after the cessation of steroid use, even if drugs are ceased before competition. This is why year round testing is needed.
  • Testosterone Precursors (Prohormones) are precursors to the synthesis of other hormones. Theorized to increase production of specific hormones in the body. Appear to have no positive benefit but, still carry some of the same potential negative health effects as steroids.
  • Human Chorionic Gonadotropin (HCG) is a hormone obtained from the placenta of pregnant women and is very closely related to the structure and function of luteinizing hormone. Detected by over-the-counter pregnancy tests. Sometimes injected into overweight females under medical supervision while using low calorie diets for weight loss. Research suggests not effective for this.
  • Insulin a potent anabolic hormone that increases protein synthesis. When elevated naturally no safety concerns, when injected could potentially lead to immediate death, coma or the development of insulin-dependent diabetes.
  • Human Growth Hormone (HGH) - a protein that is anabolic and has many important functions including; stimulating bone and skeletal muscle growth, maintaining blood glucose levels, increasing the uptake of glucose and amino acids into muscle cells and stimulating the release of fatty acids from the fat cell.
  • Random Drug Tests - using a randomized selection process to select who will be drug tested.
  • Acromegaly - a disorder where the pituitary glands produce too much growth hormone. It is characterized by a widening of the bones, arthritis, organ enlargement and metabolic abnormalities.
  • Erythropoietin (EPO) - a protein hormone that stimulates the formation of new red blood cells. When done under medical supervision, can be very beneficial. Can be very dangerous for abuse in sport as once injected, the stimulus for producing red blood cells in the body is no longer under control.
  • ß-agonists - a hormone that when released causes the airways to relax and widen. Originally developed for treatment of asthma.
  • Lipolysis - the breakdown of fat to release fatty acids.
  • Thermogenesis - producing heat due to the increase in energy expenditure.
  • Ergolytic - impairs athletic performance.

Dietary Supplements

  • Essential Amino Acids - amino acids that are not produced by the body and must be obtained by eating food. Include isoleucine, leucine, valine, lysine, methionine, phenylalanine, threonine, and tryptophan.
  • Branched-Chain Amino Acids - branched-chain refers to the chemical structure of these amino acids. Isoleucine, leucine and valine are the three BCAAs and they are responsible for increasing muscle protein synthesis. Leucine appears to be the most important.
  • Arginine is a conditionally essential amino acid. Required for the synthesis of protein and creatine and when it is metabolized the result creates nitric oxide. Supplementation of arginine appears to be largely ineffective in healthy and athletic populations.
  • Vasodilation - the widening of blood vessels. Decreases blood pressure.
  • ß-Hydroxy-ß-Methylbutyrate (HMB) - a derivative of leucine and its metabolite α-ketoisocaproic acid. It stimulates protein synthesis and decreases protein breakdown. May be an effective supplement for minimizing muscle tissue losses in a caloric deficit.
  • Muscle Buffering Capacity (MBC) - the ability of the body to clear out positive hydrogen ions. A high concentration of hydrogen ions coupled with a reduction of pH within muscle has been known to reduce performance.
  • ß-Alanine is a non-essential amino acid that is limited by itself but, in muscle is the rate limiting step for carnosine synthesis. Carnosine is reported to contribute to up to 40% of MBC during exercise.
  • Sodium Bicarbonate is an antacid that lowers pH. Increases MBC and high-intensity exercise performance. Effective but, the dose required to receive benefits, 0.3 g/kg, has been associated with miserable side effects such as diarrhea, cramping, nausea and vomiting.
  • Sodium Citrate is not actually a base but, can produce some same effects as sodium Bicarbonate without the gastrointestinal distress. More research is needed on this before recommendations can be provided.
  • L-Carnitine is responsible for carrying fatty acids into mitochondria to be used for energy. Studies investigating its supplementation have not shown any clear benefits.
  • Creatine is found naturally in the body as well as in meat and fish. Offers significant benefits. Has been shown to increase maximal strength, power and lean body mass in body trained and untrained populations. Safe and relatively inexpensive.
  • Stimulants reduce fatigue, increase alertness, confidence and sometimes result in a state of euphoria.
  • Caffeine is a stimulant that occurs naturally, is sold as a drug and is added to foods.
  • Preworkout Energy Drinks often contain caffeine and other stimulants.
  • Ephedrine is a ß-agonist that has strong thermogenic qualities. Thermogenics raise the basal metabolic rate and result in fat loss. ephedrine has many harsh side effects and is banned by most governing sports bodies.
  • Citrus Aurantium is a mild stimulant that this thought to contribute to appetite suppression and increased metabolic rate and lipolysis. There is not enough published research to recommend it. It is currently banned by the NCAA.

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Steven Mack is founder and a Certified Strength and Conditioning Specialist at the private training studio, Simple Solutions Fitness. He consults for Stronger by Science, a leader in fitness research dissemination, and is a former Mizzou football walk-on. Steven dedicates his professional life to helping people through his writing, speaking, and role as a personal trainer.