Experienced runners know that it is poor practice to ingest

Experienced runners know that it is poor practice to ingest large amounts of glucose immediately before running a marathon. What is the metabolic basis for this apparent paradox?

Solution

Carbohydrates are sugar-based molecules, and the body can use it to produce glucose. Glucose will become stored within the liver and muscle as glycogen.These are molecules for long-time energy storage that may be used when needed. But experienced runners know it is poor practice to ingest large amount of glucose before running because excessive blood-glucose level would cause the secretion of insulin, which would stimulate the synthesis of glycogen and triacylglycerols. A high insulin level would hinder the mobilization of fuel reserves during marathon.
High consumption of sugar forces pancreas to work beyond regulation, leading to type-2 diabetes.It additionally lowers stages of HDL (exact) ldl cholesterol, while growing triglycerides. Both are causes for heart attack.
More and more runners are struggling with health problems, like hypertension and diabetes, due to the high quantities of sugar they are eating.