Difference Between Red and White Muscle: Composition, Function

Red and white muscles vary in their composition and, therefore, function, allowing them to be specialized for particular activities. Red muscles, commonly referred to as red muscle fibres, contain a significant amount of myoglobin, a protein used for oxygen storage, making them red. The fibres are suited for long-duration, aerobic activities such as exercises requiring endurance. On the other hand, the white muscles, or white muscle fibres, have less myoglobin and specialize in short bursts of intense, anaerobic activity. The difference between red and white muscle fibres is therefore central to understanding how muscles are adapted to different physical requirements. This is a topic from the Locomotion and Movement chapter of Biology.

Latest: NEET 2024 Paper Analysis and Answer Key 

Don't Miss: Most scoring concepts for NEET | NEET papers with solutions

New: NEET Syllabus 2025 for Physics, Chemistry, Biology

NEET Important PYQ & Solutions: Physics | Chemistry | Biology | NEET PYQ's (2015-24)

This Story also Contains

1. What are Red and White Muscles?
2. Red Muscle Fibres
3. White Muscle Fibres
4. Comparison of Red and White Muscle Fibres

What are Red and White Muscles?

Red and white muscles are the two major types of skeletal muscle fibres identified according to their looks and operation. Muscles facilitate motion, posture, and other physiological functions of the body. Three major kinds of muscles are there in the body: skeletal (voluntary m striated), smooth (involuntary, non-striated), and cardiac (involuntary, striated).

Skeletal muscles are those used for voluntary body movements and posture. Characterised by a striated appearance, these muscles anchor into bones via tendons they are known to fatigue more easily. Slow twitch fibres, on the other hand, especially red muscles, hold many mitochondria and much myoglobin and are reserved for endurance. Fast twitch fibres, white muscles, contain fewer mitochondria and are meant for short, powerful movements.

Also Read

• Locomotion and Movement

• MCQs on Muscles and their types

• Disorders of Muscular and Skeletal System

• Neural Control and Coordination

Red Muscle Fibres

The properties of Red Muscle Fibers are discussed below-

• Characteristics: They have lots of myoglobin, so these fibres are red and well adapted for oxygen storage intensive vascularisation guarantees constant oxygen delivery with blood and the necessary nutrients much mitochondria for aerobic energy production.

• Functionality: Red muscle fibres have a slow contraction and are supposed to perform activities for long-lasting durations. It is highly enduring as it maximally uses oxygen optimally thereby resisting fatigue. From this, its source of energy is aerobic respiration, hence maintaining activity for a long while.

• Examples: It is these fibres that are dominant in the muscles of posture, for example, the spinal erectors of the back. They are also dominant in endurance-type activities such as marathon running and swimming, where contractions of moderate intensity must be maintained for extended durations.

White Muscle Fibres

The properties of White Muscle Fibers are discussed below-

• Characteristics: White muscle fibres, or fast-twitch fibres, have low myoglobin content, which gives them a pale appearance. They receive less blood supply compared to red muscle fibres and contain fewer mitochondria. This begets less-suited characteristics for prolonged activities but adequate efficiency for short, intense exertions.

• Functionality: Such fibres are formed in a way to contract quickly and exert much force and, thus, are capable of making rapid and strong movements. But, on the contrary, they have a very low duration of fatigue and, therefore, get tired very easily. They mainly rely on the process of anaerobic respiration by cells in the generation of energy and can thus support periods of activity that last very short durations of time without oxygen.

• Examples: White muscle fibres are used in muscles for fast, explosive activities, such as sprinting and weight lifting. They are important in activities that require instantaneous, high-intensity exertion rather than endurance over a length of time.

Comparison of Red and White Muscle Fibres

Also Read

Recommended video on "Difference Between Red and White Muscle"