Many young athletes take nutritional supplements often without really knowing what they are or how they work. The fact that many adult athletes take supplements does not mean that they are safe or effective for children and adolescents. Currently, nutritional supplements are not regulated for safety, purity, potency or efficacy, and manufacturers do not have to demonstrate that they are safe for children. Supplements may contain impurities or interact with medicines and there is a possibility that certain products may contain impurities that would cause a positive drugs test. This article provides information and evidence about the most popular nutritional supplements.
Young athletes often take caffeine in the form of energy drinks, sports drinks, gels or cola before and during training or competition, in the belief that it will enhance their endurance, performance, concentration, motivation and mental alertness, and mask fatigue. Studies with adults show that caffeine can allow allowing athletes to exercise longer before reaching fatigue, as it encourages the muscles to use more fat instead of carbohydrate.
But the safety and effectiveness of caffeine before and during exercise has yet to be established with children and teenage athletes. They could experience the negative side effects more than adults and end up suffering from caffeine jitters at a time when they are already nervous and anxious.
There are no official UK guidelines on caffeine for children but a review undertaken by Health Canada scientists considers 85 mg per day safe for 10 – 12 year olds. High doses of caffeine (greater than 95 mg daily) greatly increase the risks of negative side effects: nervousness, an upset stomach, difficulty sleeping, anxiety, rapid heartbeat, dizziness, and headaches in some individuals. This equates to a cup of coffee, or two cups of tea or approximately one (500ml) caffeinated sports drink or one (250ml) energy drink.
The bottom line is that there are still many unknowns about the effect of caffeine on the performance and health of young athletes. The side effects may outweigh the potential benefits of caffeine on performance. Until more research is done, caffeine cannot be recommended.
Creatine is extremely popular with adult athletes who use it for its performance boosting and muscle-building effects. However, creatine is not recommended in people less than 18 years of age, several reports indicate widespread use in young athletes.
Unfortunately, there is little information about creatine use or the potential health risk in children and adolescents. Whether it is effective or safe in the long term has not been established. It is worth considering that performance during childhood and adolescence tends to limited by mechanical factors rather than the relative contribution of the aerobic and anaerobic energy systems. A review by US researchers published in the Journal of Strength and Conditioning Research concluded that there is not enough research to support the use of creatine supplements by children and adolescents. Until the safety of creatine can be established in adolescents, the use of this product should be discouraged.
The main ingredients of energy bars are sugars (glucose, corn syrup, fructose), and maltodextrins (a carbohydrate made from corn starch). Typically, they provide between 200 and 250 calories and 40 – 45 g of carbohydrate per bar. The protein and fat content is usually low.
Energy bars are portable and non-perishable so may provide a convenient fuel source on the move. But they do not necessarily represent a better snack option than other high-carbohydrate foods, such as cereal bars, dried fruit, bananas and rice cakes with peanut butter.
Their main downside is the cost – they represent an expensive form of carbohydrate energy. Be aware, too, of the energy (calorie) content of bars. Many brands contain the same number of calories as popular chocolate and confectionary bars, and may be more than the athlete is likely to burn during the activity session! Over-consuming calories may result in weight gain.
Energy gels consist almost entirely of simple sugars (such as fructose, and glucose) and maltodextrin (made from corn starch). Some brands also contain sodium, potassium and caffeine. Most contain between 18 and 25 g of carbohydrate per sachet.
Energy gels may provide convenient re-fuelling during long hard training sessions lasting longer than an hour but you may wish to encourage young athletes to try cheaper options such as diluted juice, fruit squash (diluted 1 to 6), dried fruit (with water) or cereal bars.
On the downside, gels don’t provide hydration so, if young athletes want to use them, encourage them to drink plenty of water at the same time. A handy rule of thumb would be to follow one sachet with 500 ml of water consumed over 60 minutes; or half a gel followed by 250 ml water over 30 minutes. If they don’t drink enough, they could end up with stomach ache as the gel sits in their stomach. Some people dislike their texture, sweetness and intensity of flavour.
Meal replacement drinks supply fairly large amounts of energy, protein, vitamins and minerals in a convenient form. This makes them useful as post-training drinks or between-meal drinks. They can be prepared in advance and taken in a kit bag, then consumed after training or during break times at school. But regard them as supplemental to meals, rather than replacers of meals . Those who struggle to consume enough food to keep up their weight or to gain weight, may also want to consider adding these products to their daily food intake.
Check the ingredients on the label carefully as some products may contain substances such as creatine, which are not suitable for children and adolescents.
The main downside is their high cost, particularly those products targeted at the sports market. Mainstream ‘fortified nutrition supplements’ are significantly cheaper and offer similar nutritional benefits, so may be a more realistic option for young athletes.
Vitamin and mineral supplements
Young athletes’ needs for vitamins and minerals are higher than those of non-active children but there is little scientific evidence to suggest that supplements benefit performance. The International Olympic Committee and International Amateur Athletic Federation state that most athletes are well able to meet their needs from food rather than supplements.
Multivitamin and mineral supplements are generally safe for children and adolescents when taken in the doses recommended for them but they shouldn’t take the place of a healthy diet and certainly can’t erase the effects of an unhealthy lifestyle. Supplements that provide about 100 per cent of the recommended daily amounts are okay to take for insurance but could also be a waste of time if the athlete is consuming a healthy diet.
Young athletes should be guided to consume a varied and balanced diet. They need to recognise the value of eating a variety of foods that includes whole grains, fruit, vegetables, dairy products, and protein-rich foods. For individualised advice on nutrition, consult a qualified nutritionist or dietitian.
Protein supplements are generally considered safe but they will not necessarily build bigger and stronger muscles. This can only be achieved by combining a nutritionally adequate diet (that meets their protein needs) with a programme of resistance training.
They are not necessary for young athletes who should be encouraged to get their protein from a well-planned diet. While athletes need a little more protein than their non-athletic peers – around 1.2 to 1.4 g per 1 kg body weight – this can easily be obtained from real food. Consuming two or three portions of protein-rich foods daily – chicken, turkey, fish, meat, eggs, lean meat, cheese, milk, yoghurt, beans, lentils and nuts – should provide enough protein. Smaller amounts of protein is found in bread, pasta and breakfast cereals, which means, in practice, it is relatively easy for young athletes to meet their daily requirement.
There is good evidence that consuming drinks containing carbohydrates (sugars) during exercise lasting more than an hour can help improve performance, maintain blood glucose levels, provide fuel for the muscles and reduce the risk of dehydration and hyponatraemia (low blood sodium levels). The optimal concentration appears to be between 4 and 8g carbohydrates per 100 ml. Sports drinks also contain electrolytes, although only sodium has any performance benefit. The purpose of sodium in sports drinks is to stimulate drinking (salt makes you thirsty) and help your body retain the fluid better.
While sports drink appear to be beneficial during prolonged exercise, their cost may be prohibitive for many young athletes. Similar benefits can be gained from less expensive alternatives.
- Try mixing fruit juice with equal quantities of water. This produces an isotonic drink with around 6 g sugar per 100 ml. Add a pinch (0.5–1 g, one eighth of a teaspoon) of ordinary salt if the young athlete sweats heavily.
- Dilute 150ml – 200 ml squash with 800 ml water and 0.5–1 g (one eighth of a teaspoon) salt (optional)
- Dissolve 40 g sugar and 0.5 – 1g (one eighth of a teaspoon) salt in 1 litre warm water. Add a little sugar-free squash for flavour.
Energy drinks are essentially soft drinks with high levels of sugar and various combinations of caffeine, guarana, taurine, B vitamins and various herbs. They differ from sports drinks in that they include caffeine as well as carbohydrate. The sugar concentration is higher than that of sports drinks, around 10 – 12g per 100g, or 25 – 31g per 250 ml can, but about the same concentration as most soft drinks (e.g. cola). This is too concentrated for the body to absorb quickly, which is why energy drinks cannot be considered sports drinks. They stay in the stomach longer than plain water or sports drinks and so do not provide an efficient way of rehydrating the body.
The bottom line is that energy drinks are not advisable for young athletes before, during or straight after exercise. They have not been shown to enhance exercise performance and their high content of sugar and caffeine makes them unsuitable for proper hydration and delivery of carbohydrate.