10 June 2008
Major David Voss ED (clasp), Auckland based Specialist Renal Physician, Territorial Force Medical Officer, and NZ National Leader for the 5-nation technical panel on Human Performance discusses some of the agents commonly used in performance enhancement.
Performance Enhancement (or stimulants)
Advertising is drenched in agents claiming to enhance physical and mental (cognitive) performance. From readily available agents such as caffeine, through to amphetamines and sildenafil (aka Viagra®) the individual is bombarded daily with information. Some of the marketing claims are unfounded, unsubstantiated or simply lack evidence. Many people are using these agents without balanced advice. How can the average NZDF employee sort out the wheat from the chaff?
Performance agents (e.g. caffeine and amphetamine) need to be separated from dietary supplements (e.g. Multivitamins, minerals supplements and Centrum®) and food, fluid and electrolyte replacements (e.g. Powerade®, and Mizone®). This article addresses only the performance enhancing agents. Illicit agents (inappropriately called party drugs) such as “E” and “P” are similarly not discussed here.
Many performance enhancing agents are available in combination. In some cases the active ingredient(s) are in a quantity that is ineffective (not to a level to achieve the desired or claimed effect), or sold in a format to make the agent more easily consumed (e.g. ready-to-drink) – often with substantial price mark-up. “Performance drinks” such as “5-hour energy”, “V” or “Red Bull” probably only have one effective performance enhancing agent – caffeine. The sugars contained in these agents will provide some energy (so would a barley sugar or teaspoon of sugar). The guarana and taurine probably have no additional performance enhancement properties alone. Taurine has been shown to improve heart pump function at doses up to 8000mg. An individual will need to drink over 3 litres of V® to get this amount of taurine.
Most minerals and vitamins are in adequate supply in a balanced diet of freshly harvested (in-season), freshly prepared and eaten foods. This may not always be feasible in the “rat pack” based diet consumed by deployed military personnel. Taking supplements of vitamins and minerals from the chemist shop may be beneficial if relying on ratpacks for prolonged periods. Wet rations (hot boxes) in the field are provided wherever practicable in long duration deployments for this specific reason. Supplementing the diet with vitamins and minerals will not enhance an individual’s physical performance.
The internet is a frequent source of information on these agents. With such readily available information, the reader may be lead (or misled) to the conclusion the information is valid or from a reputable source; and use the agent. There are few good quality studies on performance enhancement agents. Users fail to report their true frequency of use or quantity. There are people with knowledge on performance enhancing agents, particularly in regards to their effectiveness and safety. I strongly encourage the reader to seek valid information prior to trialling performance enhancing agents; and before spending their hard-earned money, or risking their health.
Your local NZDF Medical Officer is likely to be the most readily available authoritative person within NZDF with the required balanced information. The MO will be able to apply the information relevant to you. The MO will allow for your health and performance demanded by your appointment within NZDF. If the MO does not have the information, he/she is able to get the information from sources within NZDF, including the author of this article. Such information may need to be worked into a training programme with your PTI.
Caffeine is an extensively studied, wide used, relatively safe and readily available human performance enhancer. It improves both physical performance (e.g. shortens run times - I can see the espresso machine at the RFL start line), concentration and alertness. Tiredness can be reduced and periods of concentration be maintained with the use of caffeine. How much caffeine is needed depends whether or not the individual is a regular user of caffeine. We have observed that up to 800mg of caffeine over eight hours (about 8 to 10 cups of coffee) can maintain alertness and physical endurance in the sleep deprived state. Such a benefit can be realised in the military setting where night watch on vessels, OP duties, and time lag with sorties (especially long flight times transgressing time zones) require the sustained vigilance.
A further benefit of caffeine is its onset of action within minutes (faster onset when chewed as a gum compared with drinking a cup of coffee), and alertness effect wears off within a few hours; thus sleep at the end of the duty is not affected. Many other (legal or otherwise) cognitive performance agents, e.g. modafinal, amphetamine and ephedrine (aka Ma-Huang) have prolonged effects or more adverse side-effects compared to caffeine.
Performance enhancing agents are no substitute for good planning, effective command, wise leadership, appropriate training and rest. Sustained operations or the demands of deployed defence force personnel may be assisted with judicious use of performance enhancing agents.
Key Points
- Many performance enhancing agents constituents have no benefit.
- Performance enhancers are no replacement for training, planning and leadership.
- Some performance enhancement agents are illegal.
- Some agents have varying levels of purity or effect. Check the manufacturer’s claims and compare active ingredients amount – the more expensive item may have no more active ingredient(s).
- Some products are marketed with levels in a dose below that which is effective.
- Take care in buying over the internet – especially from overseas; as the product you are buying may require special clearance by NZ Customs. Your hard earned money could be lost if Customs seize the product.
- Seek advice from your medical officer before using.