Okay, so what happens to physiological functioning if the training stimulus is applied before supercompensation occurs? For example, what would happen if an athlete becomes frustrated because a friend is performing better during competition than she is, and decides to train harder by running twice a day? When this athlete trains once a day, there is time for supercompensation to occur, and here is the familiar supercompensation curve. If the athlete runs the second 5K with insufficient recovery, homeostasis will barely be re-established. And here you see the second run being done when the athlete has just almost restored her body back to homeostasis, but before supercompensation. The next day the athlete does the first 5K run in the morning, but this time slightly before homeostasis has been reestablished. During this training session, the athlete will go into a deeper fatigue. The 2nd training run of the day will result in even a deeper fatigue. And over time, the physiological functioning will gradually decline due to lack of adaptation and injury or illness may result. Adaptation cannot occur without adequate recovery. Increasing the training stimulus to a 6 to 7K run once a day, thereby keeping the 24-hour recovery period, is better for long term progress of the younger athlete than reducing the recovery time. Okay, so now we can say that this timing option is not that effective for improving an athletes performance. So, what if a training stimulus is applied after supercompensation? And this can happen when the training sessions are not frequent enough. If the athlete has an injury and decides to run 5K every four days instead of every 24 hours, supercompensation will be lost during every training run. So here's her first run, then 4 days later she does a second run, and then 4 days later she does a third run. There is too much time between training sessions and in each case supercompensation has decayed. And as a result the athlete's peak performance will gradually decay back to its original point. Now for this reason, if the athlete does no training during the off season, physiological working capacity decays back to the untrained level. So, let's go back to this chart and answer our question. From a theoretical perspective the ideal timing for another training stimulus is at the peak of supercompensation, that is point B. There are variations to this rule depending on the athlete's training age, but we'll talk about those later. Mistiming of the training stimulus can occur inadvertently when athletes of different physiological capacities are group trained. A workout might be perfect for some athletes, and not hard enough or too hard for others. Only those athletes with the correct timing of the training stimulus will show performance improvement. It's not always better to group train an athlete. It's always much better to sort the athletes into groups according to similar levels of physiological functioning, even though it's convenient for a coach to group train. Timing of the training stimulus is certainly an important consideration. The goal is to usually apply the next training stimulus at the peak of supercompensation. And as you will see in later lessons however, stimulus timing for advance athletes can sometimes violate this basic rule. For beginning and intermediate athletes, the timing of the stimulus for supercompensation is a good rule to follow.