Glycogen
Definition
The stored form of glucose found primarily in the liver (approximately 100 grams) and skeletal muscles (approximately 400 grams). Liver glycogen is broken down via glycogenolysis to release glucose into the bloodstream between meals and during sleep, while muscle glycogen fuels physical activity. CGM data during exercise reflects glycogen depletion patterns — intense exercise can drop glucose by 50 to 100 mg/dL as muscles rapidly consume glycogen and begin pulling glucose from the blood.
Why “Glycogen” Matters for Glucose Monitoring
Understanding glycogen is essential for anyone using or evaluating a continuous glucose monitor. This concept directly affects how CGM devices are designed, how glucose data is interpreted, and how clinical decisions about blood sugar management are made.
This term applies broadly across all continuous glucose monitors and is foundational knowledge for interpreting CGM data, whether you are managing diabetes or using a sensor for metabolic wellness.
Related Terms
A metabolic pathway in which the liver produces glucose from non-carbohydrate sources, including amino acids, lactate, and glycerol.
A natural rise in blood glucose that occurs between approximately 3:00 AM and 8:00 AM, triggered by the body's circadian release of cortisol, growth hormone, and other counter-regulatory hormones that stimulate hepatic glucose production.
Dangerously low blood glucose, generally defined as levels below 70 mg/dL, with severe hypoglycemia occurring below 54 mg/dL.