The completion of long distance endurance races and the intensity of emotions and struggle related to it depend on whether we can maintain the efficient operation of our aerobic energy system. To do this, we need fuel and proper conditions, body temperature, and acid-base balance (pH range).
Let us take fuels into consideration: oxygen will probably be provided in sufficient amount for the total length of the track; we can only blame ourselves for the occassional hypoxia, because it is in every case the result of the improper adjustment of pace for our current fitness. This is a serious mistake, because we cannot borrow from the anaerobic system without consequences. Lactic acid, the byproduct of such energy borrowings, sooner or later stops our excellent power plant, because enzymes working there cannot conduct their activities if they are poured on by a good deal of acid. In a bit more scientific way: enzymes operating the aerobic energy system (citric acid cycle and terminal oxidation) need optimal pH environment to perform their tasks, if their environment becomes too acidic, their operation stops. Naturally, our body has a response to the accumulation of lactic acid as well: the Cori cycle is initiated, but it is an energy consuming process, and during a race we need energy for different purposes. We can tick oxygen, and if we adjust our pace and intensity properly to our fitness level, we will not have a problem with its supply.
The supply of the other fuel, carbohydrates, is a tougher task. Only limited amount of carbohydrates can be stored even by the fittest top sportspeople, so they must take care of their replenishment during the race. The problem is that carbohydrates are extremely hard to replenish efficiently. Delivering them into our stomach is not an issue. Modern energy gels spare us even from the difficulties of chewing and swallowing. UNFORTUNATELY!
Unfortunately indeed, because while we used to refresh ourselves by biscuits or salty cakes, we needed water to swallow. Life sustaining water sustains life during the process of refreshment as well. Delivering carbohydrates to our stomach is not enough, they should be transferred to the gastrointestinal tract behind the stomach, called small intestine, where they can be absorbed like other nutrients. There is one strict condition of passing the stomach: its content cannot be too dense, and it cannot have higher pressure than the osmotic pressure of blood plasma. Carbohydrates cannot be absorbed from solutions more dense than eight percent. Our stomach does not let the dense content flow towards the small intestine until it gets diluted. And it is only possible if water flows into our stomach.
Abdominal tightness and growling might be familiar phenomena, which are every time caused by stomach content supersaturated with carbohydrates. Most endurance sportspeople fail during the long distance challenges due to supersaturated stomach content. Our fellow runner from the fable also failed here. We can enhance the absorption of carbohydrates and water, significantly passing the eight percent absorption threshold, if the refreshment contains sufficient amount of Na+ (salt). This ion enhances and accelerates the absorption of carbohydrates and water. But this wonderful supplement cannot be used without keeping the limits. Sodium also has its beneficial effects primarily in the small intestine. While it gurgles in the stomach in the company of a huge flock of carbohydrate molecules, it cannot really help to deliver life sustaining water and energy providing carbohydrates into the body.
Previous parts here.
The race is yor businness, leave refreshment with Enduraid!
To be continued!