players. Today the development of strength, speed and aerobic endurance are in the focus. They are – in combination with technique and tactics – the precondition for a dynamic and attractive game. Also the referees have to adapt to these changes and have to be aware of their condition more than ever. Speed, endurance and also strength (a desicisve factor at every acceleration) have to be developed optimally, not least because of the fact that a referee, in contrast to a player, cannot be replaced during the game and therefore cannot take a rest. In this context the interaction between psychological and physical fitness has to be pointed out. Deficits in the physical education have a direct effect to the psychological capability (stress, concentration, reaction, attention, etc.). Even experienced referees cannot compensate physical problems with their experience. The training of a referee is due to the significance of particular strength factors clearly prescribed. At first the creation of a general endurance is in the focus. Endurance is the base for all other training measures. In dependence of the current lactate output curve, from where you can see the merits and shortcomings, the emphases in the endurance training are different. Referees with a weak development of the aerobic barrier have to focus their training on the basics (extensive endurance), those having weaknesses in the anaerobic barrier have to train more in the intensive area. On the basis of long-time observations and analyses the following standard values have been established in order to classify the endurance of a referee: Aerobic barrier (2,0 mmol/l) 8,5 km/h Anaerobic barrier (4,0 mmol/l) 10,0 km/h On the basis of the attached test results each referee can directly see if the reference values have been achieved, respectively in which part he/she has his/her individual weaknesses that need to be improved. The different endurance training ranges are: Regeneration/compensation A0 mostly used for recovery after heavy training effort Extensive Endurance training A1 typical training for lipometabolism, therefore you can train intensively in this area Extensive Endurance training A2 training on an aerobic basis that releases carbohydrates and fat Intensive Endurance training A3 training in the area of carbohydrates, at which the release of carbohydrates can be compensated aerobically (with the aid of oxygen) Anaerobic Endurance A4 training on the endurance limit