Playing football, which in a match situation is performed over a prolonged period of time, is a very "physically demanding" form of exercise. From a physiological standpoint, both aerobic and anaerobic energy systems are heavily loaded. To minimize the potential negative effects which fatigue can have on performance over time, an important part of any football training program is endurance training.

The movement pattern of a football player during a match is influenced by numerous variables, such as the training status of the player, the level of competition, tactical demands imposed on the player as well as on the team as a whole, the tactics of the opposing team, the result of the game, environmental conditions, etc. In general terms however, playing football is a form of intermittent exercise where very short periods (on average less than 10 seconds) of high intensity exercise are randomly interspersed with longer periods of either active (walking) or passive (standing still) recovery.

From a purely physical standpoint football specific endurance may be defined as: the capacity to perform repeated bouts of short duration high intensity exercise, interspersed at random with periods of lower intensity exercise and rest, over a prolonged period of time.

The aim of football specific endurance training should be:

• to minimize the time needed for a player to recover between bouts of high intensity exercise and therefore, increase the capacity to perform such bouts of exercise more frequently throughout a game
• to reduce the negative effects of fatigue on overall performance, especially towards the end of the game

In general terms, it is recommended that, irrespective of the level of play, the major part of the endurance training for a football player should include repeated short duration bouts (less than 10 seconds) of high intensity exercise and preferably be performed with the ball (e.g., in the form of small sided games). This is very different from the endurance training performed by endurance athletes, which consists mainly of prolonged periods of continuous exercise, who are training to cover a set distance in the shortest possible time (e.g., cyclists, runners, swimmers etc.).

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Results from scientific studies can help to obtain a better understanding of the demands and the limitations of a football player's physical performance. At www.soccerfitness.com , which has been developed by Dr Jens Bangsbo and Dr Paul Balsom, you will find educational material that will help to bridge the gap between science and practice.