ABSTRACT
In the course of the long-term development of performance (LLA) in crosscountry skiing, approximately between the ages of 10 and 20, the development of the sport-specific performance capacity is characterised by a very high dynamic. Temporarily significant changes in the level of performance (phases of increased development) can be reached in a few months or weeks. Simultaneously, you can see partially, essential differe nces in the level of performance between athletes of the same age and with similar training background. These differences are not only found between the two genders but also between retarded and accelerated athletes.
