Question

Why is the heart not fatigued even though it beats nonstop throughout the life of an individual

Answer 1

Cardiac muscle is an involuntary, striated muscle which present only in heart.
• they never get fatigue because cardiac muscle fibers are highly vascular surrounded by very rich capillary network, plenty of cytoplasm, mitochondria and rich in glycogen.
• while in skeletal muscles blood capillaries and mitochondria are not in plenty of no. And after over exercise lactic acid is form which is anaerobic glycolysis, mucles are not getting enough oxygen to work properly so they get fatigue
• but in cardiac muscle lactic acid dosn't form because large no. Of blood capillaries are present to provide enough oxygen that's why no anaerobic process occur and never they get fatigue.