s they sprint all out, and sometimes they trot comfortably. They need to train in such a way that the lactic acid buildup is delayed. To do this, they need to slow down only to a jog, a "work" recovery that doesn't quite get their breath back, then sprint again before they have completely recovereThere are many different and varied ways to interval train. You can sprint very fast and then walk. You can try sprinting very fast and then slow down to a jog. You can sprint for just a few seconds or, by slowing down a bit, go for three or four minutes. Similarly, the rest periods between sprints can be brief or extended. By changing the four components of interval training (intensity of sprint, duration of sprint, intensity of rest, duration of rest) an athlete can train the specific energy system he needs to develop for his sport.

To become a better sprinter, for instance, you need to train the creatine-P system by doing hard short sprints followed by long walks. The sprinter needs to be completely aerobic, breathing comfortably, before his next sprint so that ATP and creatine-P are fully restored. The muscles say, "If he's going to sprint that hard, we have to make more ATP than normal between the sprints." They can do that only if the rest period is completely aerobic. We call this a "rest" recovery.

A basketball player, tennis player, soccer player, or middle-distance runner wants to train his lactate system. Think about the way these athletes play. Sometimes they sprint all out, and sometimes they trot comfortably. They need to train in such a way that the lactic acid buildup is delayed. To do this, they need to slow down only to a jog, a "work" recovery that doesn't quite get their breath back, then sprint again before they have completely recovered

s can be brief or extended. By changing the four components of interval training (intensity of sprint, duration of sprint, intensity of rest, duration of rest) an athlete can train the specific energy system he needs to develop for his sport.

To become a better sprinter, for instance, you need to train the creatine-P system by doing hard short sprints followed by long walks. The sprinter needs to be completely aerobic, breathing comfortably, before his next sprint so that ATP and creatine-P are fully restored. The muscles say, "If he's going to sprint that hard, we have to make more ATP than normal between the sprints." They can do that only if the rest period is completely aerobic. We call this a "rest" recovery.

A basketball player, tennis player, soccer player, or middle-distance runner wants to train his lactate system. Think about the way these athletes play. Sometimes they sprint all out, and sometimes they trot comfortably. They need to train in such a way that the lactic acid buildup is delayed. To do this, they need to slow down only to a jog, a "work" recovery that doesn't quite get their breath back, then sprint again before they have completely recovere

d to train the creatine-P system by doing hard short sprints followed by long walks. The sprinter needs to be completely aerobic, breathing comfortably, before his next sprint so that ATP and creatine-P are fully restored. The muscles say, "If he's going to sprint that hard, we have to make more ATP than normal between the sprints." They can do that only if the rest period is completely aerobic. We call this a "rest" recovery.

A basketball player, tennis player, soccer player, or middle-distance runner wants to train his lactate system. Think about the way these athletes play. Sometimes they sprint all out, and sometimes they trot comfortably. They need to train in such a way that the lactic acid buildup is delayed. To do this, they need to slow down only to a jog, a "work" recovery that doesn't quite get their breath back, then sprint again before they have completely recovere

P than normal between the sprints." They can do that only if the rest period is completely aerobic. We call this a "rest" recovery.

A basketball player, tennis player, soccer player, or middle-distance runner wants to train his lactate system. Think about the way these athletes play. Sometimes they sprint all out, and sometimes they trot comfortably. They need to train in such a way that the lactic acid buildup is delayed. To do this, they need to slow down only to a jog, a "work" recovery that doesn't quite get their breath back, then sprint again before they have completely recovere

s they sprint all out, and sometimes they trot comfortably. They need to train in such a way that the lactic acid buildup is delayed. To do this, they need to slow down only to a jog, a "work" recovery that doesn't quite get their breath back, then sprint again before they have completely recovered. Their ATP and creatine-P are only partially replenished, so the next sprint uses more of the lactate system for energy. As you get fitter the muscles learn to handle greater and greater loads of lactic acid with less fatigue.

Finally, the endurance athlete can also benefit from interval training in developing his aerobic system. Since wind sprints are inherently anaerobic, you may be wondering, "How can you train the aerobic system by doing anaerobic work?" The answer is that aerobic enzymes increase in response to the tasks required of them during recovery. During recovery, aerobic enzymes not only replace ATP and creatine-P, they also process lactic acid. The enzymes say, "If he's going to sprint every now and then, we need to grow so that we can make new ATP faster and get rid of lactic acid faster."

In other words, the aerobic enzymes increase in response to anaerobic stress. But, they only function under aerobic conditions. Therefore, to develop the aerobic system, the athlete must exercise aerobically during the recovery period. The neat thing about training the aerobic system with wind sprints is that one of the other two systems gets trained as well. If y