In the past few years, nutrition gained a (deserved) spotlight regarding sports and athletic performance. However, when considering children, one must also take into account the role of diet on growth, maturation and development. An adequate nutrition status during childhood may have a positive impact on chronic disease prevention. It is equally important to consider that dietary habits are usually “transported” to adulthood – as so, it becomes crucial to educate children on nutrition. So what do you need to know about feeding a child athlete?
The first step is looking into the basics. Does your child eat enough vegetables, legumes and fruits? Do you usually avoid buying foods rich in sugars and fats? Is fish consumed daily? Start by identifying their dietary habits and, consequently, what needs to be maintained and/or changed. These questions can be helpful:
- Do they consume breakfast?
- Do they consume at least 3 portions of fruit per day?
- Do they eat vegetables and soup every day?
- Do they consume low-fat or non-fat dairy sources?*
- Do they eat whole grains?
- Do they avoid red meats?*
- Do they eat leaner sources of protein, such as fish and chicken?*
- Do they avoid juices and sodas?
- Do they drink enough water?
- Do they avoid products rich in sugars and saturated fats?
*if your child is vegan, these foods can be replaced by plant-based milks (e.g. soy and almond drink), legumes, soy, tofu, tempeh, amaranth, etc.
If the answer for all these questions is yes, then you have already accomplished step one, and can move forward to step two: child nutrition and sports performance.
Energy requirements during childhood and adolescence must be met to sustain performance, improve recovery, and allow growth and maturation. Each athlete has different energy needs, depending on body composition, exercise demands and growth rate. Symptoms of a low energy availability include impaired concentration, fatigue, low mood, and reduced performance. Eating an adequate diet with appropriate amount of carbohydrates, fats and protein, as well as micronutrients, ensures energy availability.
Regarding macronutrients, evidence for child athletes is still insufficient, and generally extrapolated from studies developed on adult athletes.
Carbohydrates, such as those found in fruits, whole grains, rice, pasta and potatoes, are the main source of fuel for athletes, and must be included as part of a healthy diet. However, children are believed to metabolize carbohydrates differently from adults – it seems like their glycolytic capacity is less developed. It is possible that child athletes also rely on fats as a source of fuel, at least in a higher degree comparing to adults.
Fats are essential to fat-soluble vitamins absorption, and should correspond to 25% to 35% of total energy intake. Saturated fats, which are present in fast-food, fried food, pastry products, chips and candies must be avoided. Sources of fat that can be eaten on a daily basis include fish (e.g. salmon, sardine), nuts, seeds, olive oil and avocado.
Considering protein, it is important to note its role on building and repairing muscle and tissues. One should prefer lean sources of protein, as lean meats, fish, eggs, dairy products, legumes, soy, tofu, tempeh, and plant-based milk.
Fluids are also important for health and exercise. However, there is still a need for more investigation on fluids needs for this age group. Thermoregulation differs between child athletes and adults – children seem to be at a higher risk of heat stress, probably due to a higher ratio of surface area to body mass. Furthermore, sweating capacity is lower in children when compared to adults. Some practical recommendations that can be applied in sports facilities and at home include:
- Weighing before and after exercise to evaluate fluid losses (rehydration through the ingestion of 1.5 L fluids per kg of weight lost);
- Checking urine colour;
- Considering environment when defining drinking strategies (e.g. hot weather).
When feeding a child athlete, micronutrients are crucial for growth, maturation, and development. Calcium, vitamin D, zinc and iron are minerals that require particular attention.
Calcium is involved in bone health and muscle contraction, and can be found in foods like dairy products, spinach, broccoli and fortified products. To be absorbed, calcium is dependent on adequate levels of vitamin D. The main source of vitamin D is sun exposure, followed by foods such as egg yolk and fish oil. Iron is also a critical micronutrient during this stage, being essential for both oxygen delivery and growth support. Meat, fish, poultry, eggs, and leafy green vegetables are some examples of good sources of iron.
Giving this information, it is time to associate macronutrients and fluids to the timing of training. General guidelines suggest the consumption of a meal three hours before exercise, in order to prevent gastrointestinal upset. This meal should be high in carbohydrates, moderate in lean sources of protein, and low in fats (harder to digest). If exercise is practiced early in the morning, it is recommended to have a lighter meal two to one hour before exercise (consisting of carbohydrates and lean sources of protein).
In summary, a well-balanced diet that takes into consideration energy and nutrients requirements can promote sports performance, sustain growth, and ensure the health of child athletes. Still, there is a need for more studies on this age group.
The content of this article does not constitute medical advice by a registered healthcare professional. Please consult your physician before starting any new diet, exercise or training programme.