Fartlek Training

  
This Swedish term when literally translated means speed play (primarily for running, but it can be used with all sports).  It refers to a method of training where the athlete trains as he or she wishes to, working hard sometimes and easier at others. 

It is a more flexible and in many ways more entertaining way to train, and it provides good training for sprint speed while simultaneously training distance endurance.  It it very helpful to distance athletes that need to develop the ability to sprint during the final stretch of the race (when its the hardest).

As far as we know, this training can be adapted to fit all sports and all schedules and intensities.  It can also help break up the monotony of a 'normal' workout.