Acute muscle soreness

Acute muscle soreness is the pain felt in muscles during and immediately after strenuous physical exercise. The pain appears within a minute of contracting the muscle and disappears within two or three minutes or up to several hours after relaxing it.

The following causes have been proposed for acute muscle soreness:

Acute muscle soreness is one form of exercise-induced muscle damage, the other being delayed onset muscle soreness, which appears between 24 and 72 hours after exercise.

References

Delayed onset muscle soreness

Delayed onset muscle soreness (DOMS), also called muscle fever, is the pain and stiffness felt in muscles several hours to days after unaccustomed or strenuous exercise.

The soreness is felt most strongly 24 to 72 hours after the exercise. It is thought to be caused by eccentric (lengthening) exercise, which causes microtrauma to the muscle fibers. After such exercise, the muscle adapts rapidly to prevent muscle damage, and thereby soreness, if the exercise is repeated.

Delayed onset muscle soreness is one symptom of exercise-induced muscle damage. The other is acute muscle soreness, which appears during and immediately after exercise.

Characteristics

The soreness is perceived as a dull, aching pain in the affected muscle, often combined with tenderness and stiffness. The pain is typically felt only when the muscle is stretched, contracted or put under pressure, not when it is at rest. This tenderness, a characteristic symptom of DOMS, is also referred to as "muscular mechanical hyperalgesia".