Basic concepts

Glycogen

Glycogen is the body’s storage form of carbohydrate, kept mainly in muscles and the liver.

What it does

Muscle glycogen helps fuel activity. Liver glycogen helps maintain blood glucose between meals and overnight.

Water weight

Glycogen is stored with water. When glycogen goes up or down, body weight can change quickly even when body fat has not changed much.

Practical view

  • More carbohydrate and less activity can increase glycogen and water weight.
  • Lower carbohydrate intake or hard training can reduce glycogen and water weight.
  • Fast scale changes often reflect glycogen and water, not only fat.

Source