Training glossaryHypertrophy mechanisms

Type I/II muscle fibers

Type I fibers are more fatigue-resistant; type II fibers produce more force and power but fatigue faster.

Also known as: Slow-twitch and fast-twitch fibers

In practice, muscles hold a mix of fibers, and strength training recruits that spectrum according to load, proximity to failure and the demand of the exercise. It makes no sense to promise perfect fiber-type personalization without specific assessment.

For hypertrophy, the most applicable path remains progression, adequate volume and good execution. SelfShapeAI works at that practical level: it organizes stimuli and tracks real progress without turning complex biology into a simplistic promise.

See also

Sources

Scientific references behind this entry.

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