How do slow twitch muscle fibers contract?

Slow twitch muscle fibers, also known as type I fibers, are characterized by their ability to contract slowly and sustain tension for extended periods. This is primarily due to their high myoglobin content, which allows for effective oxygen supply, and their rich blood supply, making them highly efficient for aerobic energy production. Because of this, they are well-suited for endurance activities, such as long-distance running or cycling, where sustaining activity over time with less fatigue is essential.

Additionally, slow twitch fibers are more resistant to fatigue compared to fast twitch fibers, which have quicker contractions but tire out much more easily. Hence, the key attributes of slow twitch fibers highlight their endurance capabilities, reinforcing why they contract slowly and can maintain tension for long periods without succumbing to fatigue.