Delayed onset muscle soreness (DOMS): why it happens and how to recover

Why does DOMS really happen? Let go of the "lactic acid" myth

For years muscle soreness was blamed on lactic acid building up during exercise. That is not correct. In a classic study (Schwane et al. 1983), people running on the level showed a clear rise in blood lactate yet had no soreness the next day, while downhill runners — whose lactate barely rose — developed marked delayed soreness. Lactate is cleared within minutes to an hour after exercise, whereas DOMS starts hours later. The timing alone disproves the lactic acid explanation.

The current understanding is this: DOMS is linked to microscopic damage in muscle fibres and surrounding connective tissue — plus a local inflammatory-repair response — when a muscle meets an unaccustomed load, especially during eccentric contractions (walking downhill, lowering a weight slowly, the descent phase of a squat) (Cheung et al. 2003). This is not an injury but a remodelling process; once healed, the muscle becomes more resilient to the same load. This is the "repeated-bout effect": do the same exercise a second time and the soreness is much milder.

Is it harmful, or a sign the training worked?

The presence or absence of DOMS is not a reliable measure of whether a workout was "enough." Feeling no soreness does not mean training failed, and severe soreness does not mean you gained more. DOMS is really a "novelty" signal — it tells you the body met an unfamiliar movement, volume or intensity.

• The useful side: viewed gradually, mild DOMS after a new stimulus is part of the adaptation process.
• The cautionary side: severe soreness that lasts for days and badly limits movement usually means you increased load too much, too fast — which raises injury risk. The graded-progression logic in running load management and the 10% rule applies here too.

Recovery methods: what does the evidence say?

There are dozens of "recovery" products; their evidence is not equal. Ranked honestly:

In a 99-study meta-analysis, Dupuy et al. (2018) found that massage, active recovery and some water-based methods produced small-to-moderate reductions in DOMS and perceived fatigue, with the most consistent effect for massage. For foam rolling, the Wiewelhove et al. (2019) meta-analysis showed small improvements in soreness and flexibility — helpful, but modest. Cold water immersion is its own topic: although it can lower soreness, it may suppress adaptation after regular strength training and should be used with care (see ice baths and cold water immersion).

In short: if you want to take the edge off soreness, light movement, massage, good sleep and adequate nutrition are the most reasonable and lowest-risk options. None abolishes DOMS entirely — and usually there is no need, since it resolves on its own within days.

What not to do

• Total rest is usually unnecessary; light movement eases stiffness for most people.
• There is no need to make a habit of painkillers; DOMS is temporary and harmless. Routine anti-inflammatory painkillers use may also theoretically blunt muscle adaptation.
• Chasing soreness every session under a "no pain, no gain" mindset works against controlled progression and invites overload.

When is it not DOMS? The rhabdomyolysis red flag

Rarely, very intense or unaccustomed exercise breaks down muscle cells severely and releases their contents (especially myoglobin) into the blood. This is exertional rhabdomyolysis, a medical emergency because it can threaten the kidneys (Torres et al. 2015). It must not be confused with ordinary DOMS. Seek emergency care without delay if you notice:

• Dark urine (tea, cola or blood-coloured)
• Far more severe pain and marked swelling than expected, especially extreme tightness in one muscle group
• Reduced urine output, nausea, weakness, fever
• A sense that "something is wrong," out of proportion to the exercise

This picture is more common after very high-volume/heavy eccentric sessions, extreme heat, inadequate fluids, or sudden overload in an unaccustomed person.

A note for clinicians

DOMS pathophysiology cannot be reduced to a single mechanism: eccentric loading initiates mechanical disruption at the cytoskeletal/z-disc level, followed by secondary inflammatory-nociceptive sensitisation and connective-tissue remodelling. The lactate hypothesis was disproven in the 1980s (Schwane 1983); its persistence in patient — and even clinician — language is an educational gap worth correcting. The evidence base for recovery interventions is heterogeneous: in the Dupuy 2018 meta-analysis massage shows the largest effect size (~moderate for soreness), with active recovery and immersion small-to-moderate; foam rolling (Wiewelhove 2019) yields small, short-lived effects. Keep in mind that routine anti-inflammatory painkillers and cold immersion may theoretically attenuate adaptation, particularly where hypertrophy/strength is the goal. Do not miss compartment syndrome and exertional rhabdomyolysis in the differential: disproportionate pain/tightness, markedly elevated CK (typically >5× the upper limit of normal), myoglobinuria and AKI risk; hydration and early assessment are decisive. Statin use, sickle cell trait, heat and dehydration lower the threshold.

Frequently asked questions

Related articles

• Do ice baths work? The evidence and risks of cold water immersion
• Why do muscle cramps happen in exercise? Salt or fatigue?
• Strength training: the health dose for every age and why it matters

Scientific references

This information is for general guidance only; it does not replace an examination, a diagnosis, or your physician's individual advice. Please consult a physician for your symptoms. About the author: Doç. Dr. Oğuz Yüksel — Academic Profile.