Difference Between Red and White Muscle

Criteria

Red Muscles

White Muscles

Presence of Mitochondria

They are more in number in the body

Lesser in number than they are in red muscle

Appearance

Red muscles are thinner

White muscles are thicker than red muscles

Capillary bed

Capillary bed is denser

It is less dense

Contraction rate

The contraction rate of red muscles is slower than in white muscle

The contraction rate is faster than that of red muscles

Sarcoplasmic Reticulum (SR)

They have a lesser amount of SR than white muscle

They have  more SR than red muscle

Fatigue rate

Red muscles can perform aerobic oxidation without collecting a lot of lactic acids. This helps the red muscles to contract for a long period

White muscles perform anaerobic oxidation and in the process, they accumulate more lactic acid than the red muscles. This leads to fatigue in the muscles after a short period of contraction.

Oxygen utilization

Red muscles use more oxygen than white muscles and this is one of the reasons why they are used in strenuous activities like exercise.

White muscles use a lesser amount of oxygen than the red muscles

Energy generation

They rely only on oxygen to generate energy and are thus also called slow-oxidative muscles.

They are rich in glycogen and enzymes of glycolysis which gives them the required energy.

Twitch-fibres

They have slow-twitch fibres that contract slowly for a long time without fatigue

They have fast-twitch fibres that contract faster for a short period and get tired soon.