Supplements

Vitamins, minerals, protein powders, carbohydrate gels, sports drinks and liquid meals…If you eat a varied, well-balanced diet do you really need supplements to keep you on top of your game? The use of nutritional supplements in sport is widespread. A supplement simply does just that – it supplements the diet. Within the exercise arena supplements come in many forms and guises. Table 1 gives a list of the type of commonly used sports nutrition supplements.

Table 1. Common Sports Nutrition Supplements

Sports drinks

Carbohydrate bars and gels

Protein powders, drinks and bars

Liquid meal supplements

Vitamin and mineral supplements

Ergogenic aids

Ergogenic aids are substances that aim to enhance performance through effects on energy, alertness, or body composition. Sports people are forever searching for that magic bullet that will improve performance and give them a competitive edge, but is not against the rules! Even if a supplement does all that, it could still be harmful in the short or long term.

The list of supplements and ergogenic aids used within the exercise environment is exhaustive. Therefore, we will simply concentrate on the commonly used supplements, and in particular focus on the legal supplements where there is enough scientific evidence to suggests they may have potential benefits in certain situations.

Vitamins & Minerals
Vitamins and minerals are of great interest in the sports world due to the belief that they will enhance health and improve physical performance. There is no doubt that an adequate supply of vitamins and minerals is necessary for good health, but whether exercise increases our requirement is another matter. The fact is that exercise does not particularly increase the need for vitamins and minerals.

Providing you are eating a healthy balanced diet, that is not only adequate in energy but also includes a wide variety of foods, you should have no problem getting all the vitamins and minerals you need.

Furthermore, if you are exercising and not dieting, then you will need to eat more food to meet the increased energy demand of your training. More food – providing it's a varied mixture –- means you will also be getting more vitamins and minerals. Even elite athletes, providing their diet is adequate in terms of both quantity and quality, do not usually need extra vitamins and minerals.

Most active people are highly likely to be meeting their vitamin and mineral requirements by eating a healthy well-balanced diet. However, in some cases a low-dose multi vitamin and multi mineral supplement may be useful. But, it is not necessary to exceed requirements, and in the case of vitamins and minerals – more does not mean better. You need to bear in mind that excess intakes of particular micronutrients (vitamins and minerals), particularly vitamins A and D, can be toxic.

However, people who have restricted diets may be at risk. Table 2 gives a list of common dietary situations where a low-dose multi vitamin and multi mineral supplement may be necessary.

Table 2. Diets where Supplementation May be Necessary

Diets low in energy for weight loss

Omitting foods or food groups – likes/dislikes, plus vegetarians and vegans

Lacking in a particular type of food – allergy or intolerance

Erratic and unbalanced diets – disordered eating

In particular, strict vegetarian diets, although high in carbohydrate and therefore great for providing energy fuel, can, without careful planning lead to micronutrient deficiencies in iron, calcium, iodine, zinc and vitamin B12. Therefore, in this instance, the vegetarian athlete should seek professional nutritional advice on whether supplementation is necessary.

Nevertheless, it would still be better to adapt the diet to include more dietary sources of vitamins and minerals than resort to taking a supplement. Simply taking a supplement does not make a bad diet better.

Energy Enhancers
Several nutritional ergogenic aids are effective at influencing energy. The most obvious example is carbohydrate supplements – whether in the form of powders, gels or sports drinks. Carbohydrates during prolonged exercise provide extra energy fuel to help prevent fatigue. Sports drinks deliver water and fuel to the body fast – so help to avoid dehydration and fatigue.

Several other ergogenic aids have been shown to be potentially beneficial for certain athletes. However, the long term effects are still unclear, so unless you're competing at the top level, they are probably not worth the cost or indeed the risk!

Creatine and bicarbonate supplements have been shown to be useful during high intensity work. In the first few seconds or so of sprint exercise, creatine phosphate is used as a fuel. Creatine supplementation can increase muscle creatine phosphate levels and therefore may be useful to help athletes recover quickly between repeated bouts of high intensity exercise. Alkaline salts, such as sodium bicarbonate (baking soda), can help to neutralise lactic acid and delay fatigue.

Stimulants
Caffeine is performance-enhancing due to being a central nervous system stimulant. However, if you are competing, a caffeine level in the urine above 12mg/l is not permitted. This level will be achieved by taking about 500mg caffeine – that’s about 7 cups of coffee – in a short time. Caffeine is also a diuretic so make sure you keep hydrated.

Body Composition Influencers
A variety of supplements claim to enhance performance by affecting body composition - either by increasing muscle mass and/or reducing body fat - such as protein and amino acid supplements, carnitine, chromium, hydroxymethylbutyrate (HMB), but have generally been shown to be ineffective.

Finally, bypass ‘diet and fitness assessments' that are designed to find faults in your diet that can only be corrected by taking supplements. Supplements are a more efficient way of making profit than encouraging you to eat a healthy balanced diet!