DOMS Explained

In brief: DOMS stands for delayed onset muscle soreness, the stiffness and tenderness that appears a day or two after unfamiliar or particularly hard exercise. It is caused by microscopic damage to muscle fibres as they adapt, not by a build-up of lactic acid as is often wrongly believed. It typically peaks around 24 to 72 hours afterwards and settles within a few days. DOMS is a normal part of training, distinct from an injury, and eases with gentle movement.

What is DOMS?

DOMS, or delayed onset muscle soreness, is the familiar achy, stiff, tender feeling in muscles that appears not during exercise but in the hours and days afterwards. It is especially common after activity the body is not used to, after particularly hard sessions, and after exercise involving a lot of eccentric loading, where muscles lengthen under tension, such as downhill running. It is a normal training response rather than a sign that something has gone wrong.

What causes it?

DOMS is caused by microscopic damage to the muscle fibres and the surrounding tissue during demanding or unfamiliar exercise, which triggers a repair and adaptation process. Contrary to a widespread myth, it is not caused by lactic acid building up in the muscles, which clears within a short time of finishing exercise. The soreness is part of how muscles rebuild stronger, which is why the same session causes far less soreness once the body has adapted to it.

What it feels like and when

The soreness typically begins several hours after exercise, builds to a peak somewhere around 24 to 72 hours afterwards, and then gradually fades over the following days. Affected muscles feel stiff, tender to touch and sometimes weaker than usual, and may be uncomfortable to stretch. Crucially, DOMS is a diffuse, generalised muscle ache, unlike the sharp, localised pain of an injury.

Managing DOMS

DOMS resolves on its own as the muscles adapt, and gentle movement or light active recovery often eases the stiffness more than complete rest. Building training load gradually is the best way to limit it, since large sudden jumps cause the most soreness. While many recovery tools and strategies are popular, the soreness will settle naturally within a few days regardless. Pain that is sharp, localised, severe or lasting well beyond the usual few days may be an injury rather than DOMS and should be assessed.

DOMS and your running kit at OD's

DOMS is about training load rather than equipment, but many runners find gentle active recovery and comfortable post-run footwear help them move more easily while sore. At OD's Designer Clothing we stock premium running footwear from On, Saucony and Salomon, plus recovery-friendly kit, with help in St Helens. We offer next-day delivery and free click and collect.

Please note: This guide is general information for runners, not medical advice. If you have pain that is severe, persistent or getting worse, see a GP, physiotherapist or qualified sports clinician for diagnosis and treatment.