Researchers and experienced coaching practitioners agree that periodized training is well supported by science especially the general adaptation syndrome. However, there remains considerable debate about how to effectively cycle stress and recovery to optimize the adaptation effect to sports training. There are a wide variety of periodization models available each addressing a weakness in the existing models. And it turns out, that while periodization of training makes scientific sense, implementing the philosophy so maximizes adaptations of relevant structures is a very complex aspect of training program design. Classical periodization models were developed for athletes of individual sports where there are two to three performance peaks per year. Coaches of athletes of individual sports are able to select important competition and place less emphasis on other competition. Parodization of an athlete's training is structured, so the athlete is well rested and at a performance peak for important competitions such as regional international championships. However, coaches of team sports have a problem when it comes to applying periodization. All competitions are important for the team sport athlete because each game contributes to the team standing in the league or conference. Team sports athletes must therefore maintain the highest possible performance for each competition throughout the season. In essence, every weekly game requires a peak. And sometimes the coach can get around this problem, by periodically scheduling a weaker team but this is not always possible. The classical periodization model also doesn't suit the elite individual athlete who is competing on a professional circuit. In this case, winning a competition contributes to their livelihood. So before we even begin our discussion about periodization of training, you can see that there at challenges coaches must solve when applying the philosophy to their own situation. Now on this chart here, you see the familiar supercompensation curve, it represents the physiological functioning of the body and I sometimes actually refer to it as the physiological functioning training cycle. So it's a supercompensation cycle and it begins with a training stimulus that is designed to challenge homeostasis in some way. This results in various fatiguing effects that cause the physiological functioning to decline as fatigue accumulates. And soon as the training session ends, there is a recovery of homeostasis. And therefore, the physiological functioning will gradually return to normal levels. And then, if all goes well, there is the all important supercompensational training effect. Now it takes four to six weeks to complete adaptation to a specific training stress. And at this point, little application of GAS theory to sports training suggest that a slight increase in stress is needed. And we'll call this stress two. The athlete then trains for an additional four to six weeks until full adaptation is completed to stress two. And this ends with a performance plateau. And at this point, the training is increased slightly and this is training stress number three and so on. Now theoretically, literal interpretation of GAS suggests that you continue doing this until the athlete reaches their genetic ceiling. Now, this sounds really simple, right? Well, as you know from our discussions in previous lessons when it comes to the human body, things are not quite that easy. First, we're ignoring the core training principles that are violated will result in the athlete being stuck in a performance plateau well before the genetic ceiling has been reached. And this linear approach to increasing training loads every four to six weeks eventually results in four problems. First, as the athlete adapts to a series of training stresses, very high training stresses will eventually demand longer recovery for supercompensation to occur and there will therefore be fewer training sessions per week. Second, high pain levels due to very stressful training becomes a burden on the brain. It is very difficult to prepare the body for painful training stresses for more than two to three days. The less experienced the athlete, the less pain that they are able to tolerate. And third, as GAS tells us, high stress without adequate recovery eventually results in maladaptation. The brain tries to address the stress but doesn't have the time to mobilize the necessary resources. At a minimum performance will plateau. And at worst, the athlete will succumb to illness or injury and or severe motivational problems. And fourth, the linear loading approach ignores the simple but critical see saw relationship between training volume and training intensity. And as you can see on this chart when intensity is high training volume must be low. These four issues here associated with the literal application of GAS to sports training are addressed by substituting linear loading with periodized loading.
