A spasm or cramp
A painful contraction of a muscle is a cramp or charley horse.
A painful muscle contraction is a cramp.
Such a painful muscle contraction is commonly known as cramp.
Often it is called a cramp.
A sudden painful involuntary contraction of a muscle is called a muscle cramp. This can happen due to various reasons such as dehydration, muscle fatigue, or poor blood circulation. Stretching and massaging the affected muscle can help alleviate the discomfort.
Tetanus is a life-threatening disease with uncontrolled contraction of skeletal muscle (a sign known as tetany).
A muscle spasm is the spontaneous recruitment of muscle fibers. The resulting contraction is usually painful, but it typically resolves very quickly.
The correct spelling is "cramp" and not "calf". The cramp is the involuntary contraction of the muscle and is usually very painful.
A muscle spasm caused by prolonged muscle contraction is called a "cramp." This localized involuntary contraction can be triggered by muscle fatigue, dehydration, or electrolyte imbalances. Cramps are usually sudden and can be painful, but they typically resolve on their own.
A cramp is a sudden over-shortening of a muscle. Cramps are involuntary and, often, severe. They can be extremely painful.
constant contraction of a muscle is called the muscle tone
Isometric contraction. This type of contraction occurs when the muscle generates tension without changing its length, such as when holding a weight in a fixed position.