High-intensity training is an important component of football training in modern, elite level football. Match analysis has revealed that the most successful teams perform more high-intensity activities than the less ones. Hence, football players need a high fitness level to cope with match demands. Studies on football players show that 8-12 weeks of aerobic high-intensity running training (>85% of maximal heart rate) improve maximal oxygen uptake by 5-10% and lower submaximal blood lactate concentration. Speed-endurance training improves football-specific endurance as indicated by 20-25% improvement in Yo-Yo test and the ability to perform repeated sprints.
Other studies have shown that forwards often receive the ball while sprinting or turning and cover almost 64% of their high intensity running distance with ball possession. In addition, players involvement with the ball (dribbling, short passes, successful passes) is lower in the second compared with the first half. These tactical aspects are also lower after periods of very high-intensity bouts during the match. These observations raise two points: 1) that players should perform a number of high-intensity drills while in contact with the ball, and 2) to be effective, training should provide scenarios as close to the real match situations as possible.