Vitamins, minerals, protein powders, carb 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.
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Table 1. Common Sports Nutrition
Supplements |
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Sports drinks
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Carbohydrate bars and gels
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Protein powders, drinks and bars
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Liquid meal supplements
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Vitamin and mineral supplements
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Ergogenic aids
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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.
6(i). 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.
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Table 2. Diets where Supplementation May be
Necessary |
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Diets low in energy for weight loss
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Omitting foods or food groups - likes/dislikes, plus vegetarians
and vegans
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Lacking in a particular type of food - allergy or
intolerance
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Erratic and unbalanced diets - disordered eating
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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.
6(ii). 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.
6(iii). 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.
6(iv). 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!
