I am eight years old and doing a science report on muscles. Do human muscles have white and dark muscles like chickens?

Humans do have two types of muscle fibers: Type I and Type II. Most humans have about 50 percent of each kind. Type I muscle fibers are also called slow twitch fibers. Slow twitch fibers are able to resist fatigue and work during activities that last a long time. Type I muscles are needed for endurance activities, meaning they require a big blood supply. As a result, these muscles actually look red. Type I muscles are like the dark meat on chickens. Type II are fast twitch fibers. People who have great success in tasks that need power and high-intensity speed use Type II muscles. Type II muscles can be compared to the white meat in chickens. Having both fiber types allows the body to complete a variety of physical tasks.

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