Is it true that slow-twitch muscle fibers have a high resistance
to fatigue?
Yes, it is true that slow-twitch muscle fibers have a high resistance to fatigue.
Slow-twitch muscle fibers, also known as type I fibers, are known for their
endurance capabilities.
Slow-twitch muscle fibers are characterized by their ability to generate ATP
(energy) through aerobic metabolism, which allows them to sustain activity for
prolonged periods of time. They contain a large number of mitochondria, a
network of organelles that produce energy for the cell, and rely heavily on
oxygen to produce ATP.
Slow-twitch fibers also have a high density of capillaries, which supply oxygen
and nutrients to the muscle fibers, and myoglobin, which facilitates the transfer
of oxygen from the bloodstream to the muscle fibers.
All of these features allow slow-twitch muscle fibers to contract repeatedly
over long periods of time without experiencing fatigue. In contrast, fast-twitch
muscle fibers, which rely more on anaerobic metabolism and are used for
short bursts of intense activity, have a lower resistance to fatigue.
References:
- Campbell, B. I., & Roberts, M. D. (2016). Exercise Physiology: For Health and
Performance. Jones & Bartlett Learning.
- McArdle, W. D., Katch, F. I., & Katch, V. L. (2018). Exercise Physiology: Nutrition, Energy,
and Human Performance. Wolters Kluwer.
- Gandevia, S. C. (2001). Spinal and supraspinal factors in human muscle fatigue.
Physiological Reviews, 81(4), 1725-1789.