Glucose, also known as blood sugar, is a monosaccharide that can be found in foods and the body uses it for energy.


It provides almost all the energy in the human brain and it is the body’s preferential source of energy during exercise but it cannot be eaten directly.

The body takes carbohydrates, breaks them down, derives glucose, and converts it via glycolysis to ATP (adenosine triphosphate), which is the immediate source of energy for muscle cells.

The body uses ATP for immediate energy needs or stores it in the form of glycogen to be used at later time.

Blood Glucose & Gluconeogenesis

simple carbohydrates glucose

natural cane sugar

When the blood glucose level falls below normal range (70 – 110 mg/dL) then glucose can be made in the liver from carbohydrates and protein but not from fat; no body fat can be converted into glucose but glucose can be converted into fat in the liver!

The conversion of protein to glucose is called gluconeogenesis and it happens in the liver, where proteins from the lean body mass (muscles) are converted into glucose.

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Training Zone

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