Which muscle fiber type is primarily involved in endurance activities?

Type 1 muscle fibers are primarily associated with endurance activities. These fibers are known as slow-twitch fibers and are highly efficient at using oxygen to generate energy for prolonged, low-intensity activities. Their structure allows them to support sustained muscle contractions over extended periods, which is essential for endurance sports such as long-distance running, cycling, and swimming.

Type 1 fibers are rich in mitochondria, myoglobin, and capillaries, contributing to their ability to maintain aerobic metabolism and endurance. They are well-suited for activities that require stamina rather than quick bursts of power or strength. Thus, athletes engaged in endurance training tend to develop a higher proportion of Type 1 fibers due to the repetitive demands placed on these muscle fibers during their workouts.