What causes DOMS
Delayed onset muscle soreness comes from microscopic damage to muscle fibers during unfamiliar or unusually intense exercise, followed by an inflammatory repair response — typically peaking 24-72 hours after the workout.
Why soreness isn't a reliable measure of a good workout
A well-trained muscle can grow and strengthen from a session with little to no next-day soreness, especially as your body adapts to a consistent routine. Chasing soreness as a goal often just means unnecessary extra fatigue.
When soreness might be a red flag instead
Sharp, localized pain (versus a general dull ache), soreness lasting more than 4-5 days, or pain during the movement itself rather than after are signs worth paying attention to — potentially an injury rather than normal training adaptation.
What actually helps recovery
Light movement, adequate protein, sleep, and time. Foam rolling and stretching may offer some comfort but don't meaningfully speed the underlying repair process — patience does most of the work.