Aids to Performance

Ergogenic aids

Sports people have long used performance-enhancing substances (or ergogenic aids) in an attempt to gain advantage, and many believe that most of their competitors are taking such substances. Media influences, financial rewards, and pressure from coaches, peers, and families can encourage a competitor to attempt to cheat by using drugs or other ergogenic aids. Those using such methods tend to have genuine concerns regarding their own health, but believe that taking the substances increase their chances of being successful.

Apart from supplements and drugs, other examples of ergogenic aids might include:

Psychology imagery.
Custom-fitted shoe orthoses.
Blood or gene doping.
Some of the pharmaceutical and physiological aids are outlined below.

Performance-enhancing drugs

Anabolic steroids

These are natural or synthetically-made derivatives of the hormone testosterone. Their ergogenic effects are:

Reduced recovery time after training.
Increased lean body mass.
Increased aggression (seen as a benefit in some contact sports). Anabolic steroids are used orally, as a cream, or injected.

Needle sharing carries risks of HIV, hepatitis B or C, and needle abscesses are seen from contaminated injection sites.

Despite this catalogue of adverse effects, anabolic steroid abuse is still widespread as sports people and bodybuilders risk their health in the pursuit of success. Polypharmacy and massive doses of multiple drugs is common.

Commonly abused steroids include stanozolol, nandrolone, clembuterol, and dihydrotestosterone. Tetrahydrogestrinone, a new synthetic ‘designer’ steroid, specifically produced to be difficult to detect in urine samples, was discovered in 2003. See Table 7.1 for side effects of anabolic steroid use.

Table 7.1 Side effects of anabolic steroids

Male	Female	Both sexes
Breast enlargement	Male pattern baldness	Acne
Testicular atrophy	Deepening of voice	BP
Sperm count	Enlarged clitoris	LDL/total cholesterol
	Facial hair	Risk of premature ischaemic heart disease/death
	Irregular menses	Liver abnormalities

Erythropoetin

This is a glycoprotein, produced naturally in the body by the kidneys in response to hypoxia. EPO can be prescribed in a recombinant form and is licensed to treat or be used in renal failure, some cancers, and in acquired immune deficiency syndrome (AIDS). It is administered by subcutaneous injection.

Effects of EPO

EPO exerts a direct effect on bone marrow to increase RBC production, particularly in the presence of iron.
Hb levels increase so improving aerobic performance by enhanced oxygen-carrying capacity of blood.

Adverse effects

Side effects of EPO include:

Potential life-threatening thrombosis or embolism.
Cerebrovascular accidents.
Seizures and encephalopathy.
Myocardial infarction.
Iron overload causing liver or cardiac disease.

Effects similar to using EPO can be obtained by high altitude training, blood doping, and by the use of hypoxic, hypobaric chambers at ground level.

Until 2000, EPO was undetectable. Individual sporting federations, such as cycling and triathlon have instigated blood testing with upper limits of haematocrit levels being deemed as acceptable, leading to an indirect test ‘failure’. At present, blood and urine tests are based upon transferrin receptor and ferritin concentrations.

Several sports are now also using ‘biological passports’ for some athletes that monitor for fluctuations in serial full blood counts over a period of time.

Growth hormone

GH is produced from the anterior pituitary and acts to:

Increase protein synthesis and fat breakdown.
Increase hepatic glucose production.
Stimulate the liver to produce insulin-like growth factor-1 (IGF-1), which helps muscle and bone growth.

GH is now available commercially as a recombinant product, but previously was made from pituitary glands extracted post mortem. This latter process carried a risk of the recipient developing human variant Creutzfeldt Jakob Disease (CJD). GH works synergistically with testosterone. Many of its effects rely on insulin, and the two drugs are often abused in combination. Recently, a seemingly reliable blood test for recombinant GH has allowed its direct measurement. Over-production or over-dosage of GH causes acromegaly, glucose intolerance, and hypertension.

Stimulants

Amphetamines

Sports people have abused amphetamines for over 70yrs and several high profile deaths have been linked to their use. The main ergogenic benefits of amphetamines are:

Increased awareness and delayed fatigue.
Enhancement of speed, power, endurance, and concentration.

Adverse effects of amphetamines

Amphetamines are highly addictive.
Delirium.
Paranoia.
Aggression.
Risk of cerebral haemorrhage.

Possession and supply of amphetamines in the UK is a criminal offence.

Modafinil

Recently, Modafinil, a stimulant, licensed to treat the familial condition of narcolepsy has become a drug of abuse in sport. The drug is not thought to be performance-enhancing, but there is speculation that its main use is as a masking agent for new ‘designer’ steroids.

Sympathomimetics

Sympathomimetics are readily available ‘over-the-counter’ remedies, used as treatments for the common cold. Many of these drugs are not performance-enhancing, but have been abused for years to increase energy.

Adverse effects of sympathomimetics

Anxiety.
Agitation.
Headaches.
Hypertension.
Tremor.
Cardiac arrhythmias and myocardial infarction.

Most of the drugs in this group were removed from the WADA banned list in 2004, although ephedrine remains included. Athletes who require a ‘cold cure’ should be advised always to check with a doctor before taking any such drug, even if purchased through a pharmacy. Different countries may have the same preparation on sale, but there can be a variance in the constituents which can lead to an inadvertent doping offence particularly when travelling.

Caffeine

No longer on the WADA banned list of drugs.
Has been shown to be ergogenic—appears to improve endurance.
Spares glycogen and, therefore, delays the onset of fatigue.
Exerts its effect by stimulating adipose tissue to release fatty acids, and also stimulates adrenaline production from the adrenal medulla, so in turn further facilitating fatty acid release.
Caffeine has also been shown to enhance motor unit recruitment.

Beta-2 adrenoceptor agonists

Include the drug salbutamol and related compounds.
Potent treatments used in everyday practice to treat asthma.
Orally, beta-2 agonists are not permitted in sport.
No evidence that these drugs, in inhaled form, are ergogenic in the non-asthmatic athlete.
Salbutamol (up to 1600mcg/day) and Salmeterol are allowable in inhaled form. Other beta-2 agonists require that the sports person has submitted a therapeutic use exemption (TUE), and that the TUE has been approved by their national anti-doping organization or their international governing body.
TUE must be completed by a doctor, and include a full medical history and findings of a clinical examination, as well as document laboratory evidence proving the diagnosis. The TUE should be sent to the sport’s governing body with laboratory evidence confirming the diagnosis of exercise-induced asthma (EIA). In the UK the appropriate body is UK Anti Doping (UKAD)