His body has the experience and Chris knows how to train and how to pace.

He trains with high concentration. He goes through situations in his mind that he might encounter while racing. He tries to prevent surprises that could bother him for even the blink of an eye or put him in panic. For him, training for long distance races is a question of timing and mental power, concentration. He focuses on every movement so as not to drift away when tiredness starts to kick in.
So much for Chris McCormack. Here we have another athlete, Nicole Leder, who thinks a lot a like. She listens to her body, to her exhaustion. She enjoyed the half-year break from triathlon training. In spite of the hard running schema that she accomplished during this time, it was, so she says, a break for the mind. By her results in 2007 we can see what a benefit it was to take a step away from the usual.

   Olay Sabatschus is also a guy, who listens to his body. He does not even wear a heart rate monitor. He also gives in to tiredness, when it comes. He says there is no way he can train concentrated for more than about three and a half hours a day. By concentrated he means giving neural muscular impulses, to activate the muscles. He has also experienced how a tumor can weaken the whole immune system drastically and tear down the organism’s activity. And then there are others who can suddenly access unusual power all due to a forced break because of an injury. And others train themselves half to death because they are not content with what is happening and think that more training will help that.

   Most surveys sadly only deal with measurable physiological and biochemical responses of the human organism towards training. And not with what it is like to feel good.
The question of how different training schemas influence the human sport performance has hardly been given attention. The specific physiological adaptation processes that can explain a change in power output have also rarely been discussed. The weaknesses of most of today’s training concepts mainly come from the fact that we simply do not know enough about the factors which determine our individual limits and bring exhaustion and tiredness with them. The reason being that most training and sport scientists subconsciously only accept one model of training physiology and therefore will not carry out an individually adapted mix of methods. Here I would like to discuss some different concepts on which a training schema can be based. I will be obliged to show you that an individually adapted concept mix will most suitably lead you to your destination.

Here are the models from which you can assemble your training mixture. I will not comment on the last model. If you are interested, please read my article on motivation that has also been published on the website tri2b.

• cardiovascular-anaerobic model
• energy supply/energy deficiency model
• muscle recruiting/muscle strength model
• biomechanical model
• psychological, motivation model

A muscle that is not exercised remains unexercised

Every muscle must be exercised or it will loose its strength and speed. In spite of various athletic activities, many of our 656 muscles remain unaccounted for. That is why a great runner can get sore muscles if the track profile changes. You should also train muscles which you seemingly do not need. The pelvic floor muscles and back muscles for example. Not only do many orthopedic conditions result from muscle weaknesses, they also reduce economic movement patterns. If you emphasize speed and strength you must train both, single and in combination. Endurance is always a mixture of both. Muscles make your body tension like a spring. Springs store energy, which is common knowledge from physics. This energy is important for endurance.

Economic patterns of movement lead to an improved performance.

One concept of training physiology is based on this form of energy. It is called the biomechanical model. It indicates that muscles are systems, which give back elastic energy. The skeleton muscles function as springs and produce torque. They retain mechanical energy.
Economic running belongs to this chapter for example. If the peak performance of an athlete were connected to the raised oxygen supply to the muscle, then the higher level of produced energy would also be linked to a higher thermal output. But increased heating also leads to a premature feeling of exhaustion. Heat accumulation leads to a performance drop or abortion. So it is logical to reduce the oxygen output and reduce the thermal output by a better motion efficiency.
So: Running technique, core stability, semi-specific training etc. give the muscles elasticity and tension. The muscles become a system, which will give the energy back. To improve running in an athlete who is already very fit will very probably be lead back to an improvement in his running technique. Strength and more muscles and therefore a higher oxygen output will probably not help him any further, but to reduce weight and run more efficiently. There is another advantage of a well-trained muscle (with an efficient stretching and tensing cycle). It is more resistant towards the kind of damage, which can occur by eccentric strain such as running. With this kind of muscle you can therefore train and longer and more intensively.

Summary: Less damage due to less heat in the muscle (heat also damages the tissue) and less muscle damage by eccentric mechanical strain mean a faster regeneration and the possibility to train more often without your recovery suffering.

Muscles never become acidic

Anybody who has to do with sports has heard of the story about acidic muscles. Once the muscle has gone acidic- meaning it has slipped into an oxygen deficit nothing will work anymore. We all know that and do we ever doubt the fact? And now all that is supposed to be wrong? Correct. But why? Read on if you like.

At this point 2 models of training physiology get mixed. The cardiovascular – anaerobic model and the energy supply model. The use oxygen VO2 (max) and the lactate level are parameters that are said to define the performance limits. If they do so at all then indirectly. That is why the fluctuation of these measured values is so high. This cardiovascular- anaerobic model is the most popular concept for training by far. It is based upon the work of the British A.V. Hill from the 1920s. But even Hill had clearly realized that the first muscle to become anaerobic must be the heart.
The endurance performance is limited to the stroke volume of the heart in this model and the linked oxygen transport capacity into the muscles. Effects of training are explained by a raised number of capillaries in the muscle, more mitochondria in the muscle and an appropriate adaptation of the heart in terms of heart rate and stroke volume. So training builds up cardiovascular fitness by transporting more oxygen and therefore having more to dispose of. The postponed raising of lactate in the muscles and blood is put in direct context to these facts and so is the shifting of the aerobic – anaerobic threshold that is put on a level with the appearance of exhaustion symptoms.
In the same sentence is mentioned that an optimized muscle can use more fat for the production of high energy ATP. So we conclude that the carbohydrate buffers are spared and the endurance performance rises. Of course these training induced changes to the heart, the vessels, the skeleton muscles and the metabolism are proven by studies. The only question remaining is, if they really stand in direct correlation?

The heart is also a muscle, it would become acidic first

If this model were 100% true, the heart would suffer from the oxygen deficiency first and become acidic. The results of an acidic or totally exhausted heart would be fatal. Heart patients know how bad a heart feels when undersupplied with oxygen. A strong burning pain arises in the heart region (angina pectoris). Not a single healthy athlete at his limits suffers from this pain.
Until this day there has not been a survey to prove that the muscles are undersupplied with oxygen or blood and therefore forced into anaerobic labor. We are talking about those same muscles, which we keep such a close eye on whilst training and will not even begin to discuss the remaining organs. You cannot use a performance dropout at great heat or great height as an indicator for an acidic muscle either. A healthy heart will never go acidic even at peak performance. Obviously our limits are reached as a part of a regulation process before the heart can reach a threatening state. So at great heights were the air is thin the phenomenon of anaerobiosis of the muscles must show quicker. But it does not. It is just the other way round. The blood lactate concentrate sinks with increasing height and strain (lactate-paradox). The maximum heart rate and the stroke volume also sink at great heights under athletic strain. So a performance dropout at a great height is the result of muscle contractions falling distinctly under aerobic conditions. One other interesting remark: the heart rate sinks with increasing height. That is exactly the opposite of what one would expect. So at far heights the lungs supply could become a limiting factor.

The energy supply of the muscles is not bottleneck when increasing the endurance performance

Regardless of if its carbo loading, pasta parties, dextrines, jellies, or soft drinks made of monosaccharide, the logic behind these actions is always the same. Give the body quickly disposable energy. Carbohydrates or glucose count as highly efficient transport molecules for the high energy molecule ATP which is essential for muscle contractions. So besides an oxygen deficit, the ATP supply could also be a limiting factor for increasing muscular performance. An ATP deficit could be a reason for fatigue and exhaustion.
After this training physiological approach, the goal of every training must be the adaptation of the energy supplying systems in the body to the demands of our sport. We must convert the energy as economical as possible. The high energy phosphate compounds, the carbohydrate metabolism which is independent from oxygen, the aerobic carbohydrate metabolism and the oxygen dependent lipometabolism all belong to the metabolic paths which must be exercised.
Considering all this, the athlete who can generate the most ATP most efficiently from the metabolism, which dominates his sport is the most powerful. That is why we assume that a sprinter is mostly capable of gaining ATP out of the intramuscular phosphate buffers and the oxygen independent glucose (carbohydrate decomposition) whereas an ultra marathon runner is the best if he can get his energy from the oxygen dependent lipometabolism. In an instant, the muscle quits its job when the ATP is gone. In this case we are speaking of numb muscles. But studies under extreme circumstances have shown that the ATP concentration never sinks below a level of 60% of the quiescent value. The cell ATP very rarely goes under 70%. The assumption is simple: ATP has nothing to do with the process of exhaustion and limits. By the way, the pH-level which is an indicator of how acidic a muscle is, fluctuates so severely between individuals, that it could not be used as a value performance limits. Moreover a survey resulted in the fact that neither lack of lactate or ATP can lead to a performance dropout. The real reason was a faulty connection of muscle agitation and contraction. So the model that puts a energy supply deficiency to the muscle in its center, has just as many flaws as the "oxygen supply" model.

Empty carbohydrate buffers do not determine the performance limit

The results on the studies concerning this topic are also not distinct. But this does not mean we must doubt the importance of carbohydrates. Just do not lift it above common sense. Generally we say that when the carbohydrate reserves in the liver are emptied the limits are reached. So why do athletes recover from hypoglycemia so quickly and are immediately capable of continuing their training? Of course many investigations result in a connection between depleted carbohydrate reserves in the muscle after long strain and existing exhaustion. But by no means does this indicate a liner-causal relation. The study results on carboloading are also disputable. The placebo effect cannot be eliminated. There are also trials with athletes who quit the training because of exhaustion after about 4 hours following carboloading and still had the same concentration of carbohydrates as an hour before when they had not felt exhausted yet.
No doubt, carbohydrates are an important fuel but surely they are not the only reason for exhaustion, performance dropout and performance limits of an athlete. Up to know no survey could prove the fact that training increases the endurance performance because of higher carbohydrate buffering in the body.

This model cannot explain performances that must be accessed in an IRONMAN especially the run at the end. A medium intensity run would not be possible if a buffer deficiency was at hand. Laboratory analysis suggests that an athlete must have totally emptied his carb buffers when cycling the bike track with an average of 40km/h. But still the best run a pace of 16 km/h. That is an intensity of > 66% of VO2 max. An endurance performance of up to 6 hours exceeds the muscle and liver buffer capacity by up to 100%. There are debates on a possible burning of lactate in the inactive muscles. A verisimilar theory postulates that the athlete that can burn fat in a more optimal manner can access the better performance.

Concentrated training can intensify neural muscular impulses

Every muscle requires an impulse from the central nervous system for contraction. These stimuli determine how many muscle fibers are activated. You will be surprised to hear that only about 20% of the muscle is activated in the stage of high strain. We also speak of a fatigue and exhaustion that is triggered by the central nervous system, a so-called central exhaustion or fatigue.
Is this the famous tiredness of the mind which many athletes talk about? It is proven that the central nervous drive decreases when the muscle grows tired. But neither requires an anaerobic situation or empty buffers. Another indication for the central nervous component of exhaustion and fatigue is the fact that less muscle fibers are recruited by the central nervous system at great heights. The same counts for high temperatures. “Pre cooling” improves the performance just as “pre warming” worsens it. This central fatigue kicks in before a lethal situation can arise in the organs in contrast to the peripheral fatigue which determines the limits in other models. So we have safety margins to protect the heart, to ensure the ATP supply and generally hold the body in balance. Not just plain training but concentrated training changes the efficiency of the exercise and raises the resistance towards exhaustion. Neural muscular pathways must also be trained.

Circuits in the central nervous system determine the performance limits

A nice, and in my opinion very logical comparison that supports this approach is that of an athletic peak performance and that of an extremely dangerous disease that often leads to death. At the same time this shows us that the observation of measuring parameters alone can be rather misleading. The disease is called SIRS (systemic inflammatory response syndrome) and can have many causes. Two or more of the following criteria must be fulfilled to diagnose a SIRS: body temperature over 38°C, heart rate over 90/min, breathing rat over 20/min, leukocytes over 1200/nl or under 4000, immature leukocytes over 10%. You will find the same indications in a marathon – runner without being the least bit threatening. So we perceive how important the context of the measurement is and that values can be a surrogate of many components. And we can also see that obviously the healthy regulation processes that happen behind the measurement, are crucial and not the measurement itself.

Are there central switches? There is surely a whole complex network of circuits, central peripheral that ensures that no organ or organ system is driven to a lethal boundary. Therefore the performance limit is a result, which is calculated out of all the mentioned parameters. It is not merely a final result but a constantly running calculation. Training influences this result and changes the variables and the timing of the circuits towards safe boundaries.
You will have noticed that it is very difficult to decide on one single training concept on hand of this information. All the facts lead us back to the beginning and the realization that there is a bit of truth in all of it. To improve the endurance performance and access this at a fixed moment in time as well is a tricky business and a mission of training. More and more coaches, recommend listening to your inner voice and find out what it is like to feel good and then to train according to that feeling.
Chris McCormack also points that out. He says: “The body is a smart thing. And it is one body, everything is related to everything, people tend to forget this.”
That is why there is not only one correct way of reaching a goal. To feel good is difficult. The feeling cannot be described with a heart rate monitor or stuffed in with carbohydrates. It is the art of finding out in training which mixture your body needs to find that wellbeing which leads to an ideal performance.

Many thanks for the various inspirations to TD Noakes, University of Kapstadt, South Africa