Doctor's Reference Guide To Dietetics

Competitive Sports


General information:

Diet is an important factor in determining performance. Carbohydrates, proteins and fluids have a direct impact on athletic performance. An adequate diet and managing body weight and body composition have an indirect impact on athletic performance for those in endurance, strength, and game sports.


Best time to refer to the dietician:

  • athletes who train intensively for 1-2 hours at least 3 times a week.


Relevant information for the dietician:

  • Symptoms: gastrointestinal problems, fatigue, anorexia, sometimes injuries
  • Laboratory tests: glucose, urea, Hb, ferritin, hematocrit, albumin, sometimes folic acid, vitamin B12
  • Other: height, (changes in) weight, fat percentage, exercise data (level of training, duration of training, intensity).


Aims of the diet:

  • contribute to improving the athletic performance
  • prevent/reduce symptoms
  • for injuries: promote recovery and rehabilitation
  • maintain/achieve a healthy competition weight
  • prevent eating disorders


Characteristics of the diet:

  • complete sports nutrition (50-60% of caloric intake in the form of carbohydrates, 1.2-2 g protein/kg of actual body weight, and at least 20% of caloric intake in the form of fat) customized to the individual athlete
  • Extra fluids: 2-5 L, depending on exertion and climate.


Treatment time:

  • Care level 2, see “Dietician’s working methods.”


Specific remarks:

  • Nutritional supplements may mask any nutrient deficiencies.



Geel van A, Hermans J. Voeding en Sport. Baarn: Tirion Uitgevers BV. 2009


Loon LCJ. De menselijke motor: voeding als energie. Geneesk Sport 2002;5(3):7-10


Maughan RJ (red.). Nutrition in Sport. Volume VII of the encyclopaedia of sports medicine. Oxford: Blackwell Science: 2000


Maughan RJ, Burke LM. Sports Nutrition. Oxford: Blackwell Science: 2002


McAardle WD, Katch FI, Katch VL. Sports & Exercise Nutrition. Philadelphia: Lippincott, Williams & Wilkins: 1999


Competitive Sports was updated by Anja van Geel, Quirine Altorf and Joris Hermans, writing also on behalf of the Vereniging Sportdiëtetiek Nederland.


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