Question

List the differences between type I, type IIa and type IIb and IIx fiber types

Answer 1

A muscle is composed of muscle fibres. These muscle fibres can be divided into type I, type IIa and type IIb and IIx fiber types.
The difference between these muscle fibres is as follows:

Type l	type lla	type llb	type llx
Slow twitch	moderate to fast twitch	Fast twitch	very fast twitch
High fatigue resistance	moderately fatigue resistant	Low fatigue resistance	Very low fatigue resistance
very high density of mitochondria	high density of mitochondria	medium mitochondrial density	Low mitochondrial density
High capillary density	intermediate capillary density	low capillary density	low capillary density
Low power	medium power	high power	very high power
Used for aerobic activity	used for long anaerobic activity	used for short anaerobic activity	used for short anaerobic acti