Bar-Or, O. (1996). Developing the prepubertal athlete: Physiological principles. In J. P. Troup, A. P. Hollander, D. Strasse, S. W. Trappe, J. M. Cappaert, & T. A. Trappe (Eds.), Biomechanics and Medicine in Swimming VII (pp. 135-139). London: E & FN Spon.

A training program must take into account a child's health and well-being (short and long-term), unique physiological responses to exercise and training, specific nutritional requirements associated with growth, and a variety of psychological considerations. The team that prepares the child athlete must include the parents. This paper focuses on the physiological requirements.

  1. When calculated per cross-sectional area of muscle, strength is similar in children, adolescents, and young adults.
  2. Maximal aerobic power, when expressed as per kg body mass, lean leg mass, or total blood hemoglobin, is similar across maturational groups.
  3. Peak muscle power and local muscle endurance, both reflecting anaerobic muscle characteristics are lower in children even when corrected for body or lean muscle mass.
  4. As children mature through adolescence to adulthood there is a growing ratio of anaerobic to aerobic peak power.
  5. Children's athletic performances are deficient in power/strength events and less deficient in aerobic activities but in swimming there is a similar difference between children and adults in both sprint and endurance events.
  6. Children have a higher oxygen uptake (VO2) per kg of body mass compared with adolescents who have greater values than adults. A cause of these differences could be that children have a higher mechanical cost of locomotion due to wasted energy as agonist and antagonist muscles work against each other to a greater degree.
  7. Children recover faster following both aerobic and anaerobic activities.
  8. Children are less tolerant of heat and cold with core temperatures changing faster than those of adults.
  9. Undergoing training regimens similar to those practiced by adults, produces trained states in prepubescents.
  10. Children mainly improve in the economy of movement when training. The oxygen cost of activity decreases without any increase in VO2max.
  11. Prepubertal girls and boys respond to resistance training in percentages of improvement similar to adolescents and adults.
  12. Children increase strength without an increase in muscle bulk.
  13. Whether strength training improves sporting performances in children is still a debatable topic.


  1. A child's suitability for a specific event is rarely established prior to puberty and so a training regimen for a child athlete should be as varied as possible.
  2. There is no proof that specialized training in children will yield long-range benefits.
  3. There are no physiological or medical reasons why prepubescent girls and boys should not compete against each other, even in contact and collision sports.
  4. Children take longer than adults to acclimatize to warm (and cold) environments. Periods of adaptation should be longer and contain lighter training loads than those for adolescents or adults.
  5. Children should be encouraged to always drink above perceived needs to avoid dehydration.

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