Soccer is perhaps the most demanding of all sports.
In the modern game (at any level) soccer training and conditioning is essential.
Few sports are played on as large a playing field, lasting as long and without regular rest periods.
Players cover 8-12km during a match, consisting of 24% walking, 36% jogging, 20% coursing, 11% sprinting, 7% moving backwards and 2% moving whilst in possession of the ball (1).