Although the results of the AIS physiological testing reveals that a high average level of fitness can be maintained by a squad for the duration of a season by concentrating on game-specific training during the season, practical experience has also shown that the more traditional, basic, conditioning work is needed by layers in certain circumstances, for example, when certain players need to develop speed, power or agility. At the AlS, 2-3 sessions weekly ore devoted to weight training, sprints, and plyometrics, designed to improve acceleration, speed, agility and overall strength. These components are necessary in the modern game, since even the most highly skilled player can find themselves brushed off the ball all too easily by aggressive defenders, and there is also some evidence that the more robust player is more likely to survive the season without injury. There is also the need to address individual player's weaknesses; the physically inferior players may need resistance training to increase their muscle mass; a player with poor endurance (especially if they are a midfielder or outside back), should be encouraged to undertake additional aerobic conditioning, above their normal training. Some times game-specific training will be insufficient to bring a player up to the necessary level of fitness required because of the stop-start nature of training, and because all-round endurance development requires a spectrum of training ranging from protracted continuous work to regular, disciplined, interval sessions.