NUTRITION – Ergogenic aids in sport

Ergogenic aids in sport – do they really work?

THERE has been some media debate in recent months regarding the pros and cons of athletes taking performance enhancing drugs. Well let’s take a look at just a few of the products that athletes are commonly using today and see if they could be useful in the sport of Orienteering.

Firstly, we must define the term nutritional ergogenic aid - it is a supplement containing a nutrient or food-related substance, consumed in the hope of an immediate boost to performance. Generally, it aims to produce a pharmacological or legal drug-like action to improve work output. It should be backed up by a proposed mechanism that has been tested in scientific double-blind trials. However there is often reliance on theoretical or anecdotal support rather than documented scientific evidence. Ergogenic aids tend to be in or out of fashion and they are often extremely expensive.

In common usage by sport enthusiasts today are products like caffeine, creatine, bicarbonate, glycerol, colostrum, carnitine, branchedchain amino acids, CoQ10 and Ginseng to name but a few. Of these, only the first four really have any scientifically proven ergogenic effects.

Caffeine use has been around for over 100 years and its stimulant effects are well known. A dose of some 300-500 mg of caffeine consumed in the hour before an event may improve performance in prolonged aerobic exercise. This may be due to several factors including the sparing of muscle glycogen by increase in fat usage as a fuel, as well as the general increase in nervous stimulation which might mask fatigue. However, there are people who respond adversely to caffeine and those who don’t respond at all, so it is really only useful if you know you are a ‘caffeine responder’ – someone who experiences a pronounced performance boost from consuming it.

Creatine is still under the process of investigation, but there have been some reputable scientific studies showing benefits in athletes taking creatine phosphate supplements for particular short sprint-type sports lasting between 1-10 seconds. Studies have shown that creatine can improve recovery between repeated bouts of high intensity exercise but may not enhance the overall performance of aerobic or endurance sports.

Bicarbonate has also been shown to be of use in high intensity anaerobic events lasting 1- 7 minutes, such as 800-1500m runs, 200-400 m swims and some rowing events. Bicarbonate acts as a buffer to help mop up the excess hydrogen ions that accumulate in the muscle with such activity.

Many of the other ergogenic aids rely heavily on anecdotal evidence – an athlete’s testimony that it works, or on heavy advertising that is not scientifically based. Colostrum is one such example. It may be very good for new-born babies (as it is the mother’s first milk) to promote immunity and important growth factors, but there is really no good evidence to show that it can enhance performance, recovery or positively affect body composition, as has been promoted in its marketing. Colostrum supplementation is an example of just how expensive ergogenic aids can be - costing up to $70-$100/week.

Glycerol is the one ergogenic aid that could possibly be of use in Orienteering, but mainly when competing in very warm and particularly humid conditions, when fluid availability is limited. Oral intakes of glycerol are rapidly absorbed and slowly metabolised by the kidneys and liver. A high fluid intake with the ingestion of glycerol can produce fluid retention of up to 600ml by reducing urinary output. The most effective intake to produce glycerol hyperhydration is 1-1.5g/kg body weight (BW) glycerol with 25 – 35ml/kg BW of fluid.

Glycerol can be brought as glycerine solutions or special hyperhydration supplements. It may help in sports that contest fluid status and thermoregulation i.e. exercise in hot, humid atmospheres or exercise at high intensities, where sweat loss is elevated and rehydration is unavailable. Retaining that extra volume of fluid in the body may make the difference between being hydrated enough to think your way clearly to the next control, rather than making one of those horrendous errors that creep in late in a run.

In summary, I would have to say that many athletes spend unnecessary (multi)dollars on supplements and aids that have no possibility of enhancing their performance. There is no magic quick fix that can make up for lack of training, fitness, talent, adequate sleep and recovery, optimal training diet or strong mental attitude in the athletic field. All of these factors have been proven to positively affect performance. My recommendation would be to work hard on all of these before resorting to any pills or potions.

If readers have any questions about nutritional ergogenic supplements which they may be taking or considering, Gillian Woodward has offered to provide answers in the December edition of The Australian Orienteer. Just e-mail your questions to The Editor, mikehubbert@ozemail.com.au by October 7th.