Question

Carbohydrates are an important macronutrient for fueling muscles. During exercise, where can the body get carbohydrates?

1) Glycogen stored in the muscle cells
2) Glycogen stored in the liver cells
3) Glucose available in the bloodstream
4) All of these are correct.

Answer 1

The body can get carbohydrates from glycogen stored in muscle cells, glycogen stored in liver cells, and glucose in the bloodstream during exercise. All of these are valid sources, and athletes often 'carb-load' to maximize these stores for energy.

Step-by-step explanation:

During exercise, the body can obtain carbohydrates from several sources. These sources include:

1. Glycogen stored in muscle cells.
2. Glycogen stored in the liver cells.
3. Glucose available in the bloodstream.

All of these are correct (option 4). Muscle glycogen is used primarily by the muscles themselves. Liver glycogen can be broken down into glucose and released into the bloodstream, maintaining blood glucose levels, which is particularly crucial during prolonged exercise. Finally, the glucose present in the bloodstream can be derived from carbohydrates ingested through diet and is readily available for use by cells for ATP production. Engaging in carbohydrate loading before competitions is a common strategy for athletes to maximize their glycogen stores and ensure they have sufficient energy for endurance activities.