APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -Cardiac muscle: Cardiac muscles are only in your heart. They help your heart pump blood throughout your body. They’re involuntary muscles that your autonomic nervous system controls.

Detailed explanation-2: -Rapid, involuntary contraction and relaxation of the cardiac muscle are vital for pumping blood throughout the cardiovascular system. To accomplish this, the structure of cardiac muscle has distinct features that allow it to contract in a coordinated fashion and resist fatigue.

Detailed explanation-3: -Cardiac muscles are said to be involuntary because they are not controlled by our will. These muscles are found in heart and are the only muscles which work throughout the life without getting tired or fatigue.

Detailed explanation-4: -Final Answer: Hence, The muscles which never fatigue are the Cardiac muscles.

Detailed explanation-5: -This is primarily because the heart is made of cardiac muscle, consisting of special cells called cardiomyocytes. Unlike other muscle cells in the body, cardiomyocytes are highly resistant to fatigue.