Abstract
Youth participation in sports shows upward tendency. There is a strong interaction between nutrition, growth / development and success achievement in sport. Some physical aspects of the physiology of children aged 7-12 years, are not sufficiently clear. Needs assessment of children for macro/micronutrients hinders physiological variability of growth during puberty. However, we can point out the general needs of this population: 1) rehydratation in order to maintain optimal function of the cardiovascular system, based on the principles that apply to adults, 2) meeting the needs for energy and macronutrients. Daily energy needs, aged 9-13 are 1400-3000 kcal, depending on gender, stages of puberty and physical requirements. The recommended protein intake is 1,5-2,2 g / kg of BM. The intake of carbohydrates should be above 50% of daily energy needs. Intake of essential fatty acids should be in accordance with the recommendations. 3) Optimal input of micronutrients provide satisfaction of energy needs and implementation of balanced diet. The most common mineral deficits, with young athletes are related to iron and calcium. Supplementation with vitamin-mineral beneficiary substances showed no effects on growth and physical achievement.