It is a phenomenon that has long been associated with increased physical exertion. DOMS is typically experienced by all individuals regardless of fitness level. It is a normal physiological response to increased exertion, and the introduction of unfamiliar physical activities.
DOMS is often precipitated predominantly by eccentric exercise, such as downhill running, plyometrics, and resistance training.The typical symptoms often associated with DOMS include strength loss, pain, muscle tenderness, stiffness, and swelling. They start within the first 48hr of exertion and can last up to 10 days.
NSAIDs, supplements and warming up have been mentioned as proposed interventions but it seems like only warming up really seems to deliver.
Warming up increases muscle temperature that improves muscle function allowing for more efficient muscle contractions, which deliver increased speed and force.
Bodybuilders, next time you are in the gym, quit that non sense of NO PAIN NO GAIN. Seek out medical attention because you might be experiencing DOMS.