Delayed Onset Muscle Soreness (DOMS)

DOMS happens after significant workouts secondary to a disruption of structural proteins in muscle fibers and connective tissue, subsequent tissue inflammation and increased perceived fatigue. 

A meta-analysis reviewing 99 studies showed that the most powerful techniques for reducing inflammation and perceived fatigue were massage and cold exposure. 

Dupuy, O.  Frontiers in Physiology.  April 2008.  An evidence-based approach for choosing post-exercise recovery techniques to reduce markers of muscle damage, soreness, fatigue, and inflammation: A systematic review with meta-analysis.