This particular subject is quite simple once we address the fundamentals and disregard the majority of the unecessary or inapplicable issues which complicate the primary emphasis of the subject.
The goal of your nutritional intake during exercise activity is to sustain the increased energy requirement due to various training factors such as intensity, duration and frequency. These factors combined equal your total training volume. As exercise intensity increases, greater emphasis is placed on carbohydrates to be utilized as fuel. Anaerboic metabolism occurs during high intensity exercise and the majority of energy derrives from the conversion of muscle glycogen to lactic acid. Glycogen stores are rapidly reduced during short term high intensity intermittent exercise due to the overall energy demand and limited stores. Within 20 minutes, glycogen stores decrease to approximately 80% on average. Therefore, it's imperative that your carbohydrate intake is adequate in order to sustain the training load necessary to induce the necessary physiological stimulus which is needed to improve and/or maintain performance. As previously mentioned, significant reductions in glycogen stores, muscle and liver, take place during anaerobic activity. This is why it is essential to supply and replenish your carbohydrate stores. If this is not accomplished to an optimal extent, the result is an automatic reduction in your overall performance. More specifically, due to the inadequate nutritional intake, your training intensity and/or duration decreases as your body is not able to meet the demands elicted by the exercise activity. This ultimately impairs progress via a decreased adaptive physiological response from your body since the required stimulus is not generated in order to increase or maintain performance.
Jenetic
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