Question

Endurance training can make muscles more resistant to fatigue. What types of changes occur within the muscle to allow for this? Explain.

Answer 1

there are different types of muscle fibers in the body, which are classified based on how they produce energy. Yes, the different muscle fibers can be trained using specific exercises designed to focus on how they create energy or generate force. While a variety of types of muscle fiber have been identified, including type I, type IC, type IIC, type IIAC, type IIA, type IIA and type IIX, they are generally classified as being either slow-twitch or fast-twitch

Endurance training primarily work the slow twitch (type 1) fibers and develop such fibers in their efficiency and resistance to fatigue , because slow twitch muscle fibre have the following property

slow-twitch, or type I, muscle fibers:

1. Slow-twitch fibers contain mitochondria, the organelles that use oxygen to help create adenosine triphosphate (ATP), which is the chemical that actually fuels muscle contractions, and are considered aerobic.
2. Slow-twitch fibers are also called red fibers because they contain more blood-carrying myoglobin, which creates a darker appearance.
3. Because they can provide their own source of energy, slow-twitch fibers can sustain force for an extended period of time, but they are not able to generate a significant amount of force.
4. Slow-twitch fibers have a low activation threshold, meaning they are the first recruited when a muscle contracts. If they can’t generate the amount of force necessary for the specific activity, the fast-twitch muscle fibers are engaged.
5. The tonic muscles responsible for maintaining posture have a higher density of slow-twitch fibers.
6. Steady-state endurance training can help increase mitochondrial density, which improves the efficiency of how the body uses oxygen to produce ATP.