Muscle Soreness — Acute vs. DOMS
Sources and review status
Review pending — this text hasn’t been signed off by a reviewer yet.
See this lesson’s sources0% read · 3 min left
Soreness comes in two forms: acute discomfort during or right after exercise, and delayed-onset muscle soreness (DOMS), which builds over the next day or two and usually peaks 48–72 hours after unfamiliar or eccentric-heavy exercise.
Detail
People who do resistance training commonly experience discomfort, soreness, stiffness, or pain. These afflictions fall into two general categories: those that occur during and immediately after exercise (which may persist for several hours), and those that usually do not appear until 24 to 48 hours later (Alter, 1996).
Acute soreness — pain felt during and immediately after exercise. The original reference attributes it to the build-up of exercise end products, such as lactic acid, and to tissue edema (fluid shifting from the blood plasma into the tissues, the "pump up" feeling). Lactic acid is one of the historical theories for soreness, not an established cause of DOMS (Cheung et al. 2003; see Lactic Acid (Glycolytic) System).
DOMS (Delayed-Onset Muscle Soreness) — soreness that does not appear straight away, hence the name. The original reference describes it as felt between 12 and 48 hours after a strenuous bout. Current reviews put the peak at 48–72 hours after exercise (Hotfiel et al. 2018).
- Cause: small-scale (ultrastructural) damage to muscle fibres from eccentric or unfamiliar exercise, followed by protein breakdown and a local inflammatory response (Hotfiel et al. 2018). Eccentric actions cause this damage more often and more severely than other muscle actions (Cheung et al. 2003).
- Signs: reduced force, painful and restricted movement, stiffness and swelling (Hotfiel et al. 2018).
- When it's common: returning to training after time off, or starting a new type of activity (Cheung et al. 2003). Introducing eccentric or new exercises gradually over 1–2 weeks reduces the disruption (Cheung et al. 2003).
Note: some degree of soreness is often experienced by those who have not previously exercised or stretched — the penalty for being inactive. Well-trained athletes who work out at higher-than-usual difficulty can also become sore.
Key facts
- Two categories: (1) during or immediately after exercise (lasts several hours); (2) delayed onset, building over the following day or two.
- DOMS usually peaks 48–72 hours after exercise (Hotfiel 2018); the original reference gave 12–48 hours.
- Cause: ultrastructural muscle damage from eccentric or unfamiliar exercise, then local inflammation (Hotfiel 2018).
- Acute discomfort: historically attributed to end products (e.g., lactic acid) and tissue edema ("pump up"); lactic acid is not the cause of DOMS (Cheung 2003).
- Introduce eccentric or new exercises gradually over 1–2 weeks (Cheung 2003).
- Affects the previously inactive and well-trained athletes working harder than usual.
Connections
- Three Hypotheses of Muscle Soreness — the three explanations for soreness.
- Eccentric (Negative) Muscle Action — eccentric work as the primary instigator of DOMS.
- Lactic Acid (Glycolytic) System — lactic-acid end products in acute soreness;
that module's
verification_notecovers the broader 2026 update on lactate and fatigue (it's not the culprit it was once thought to be). - Recovery and Rebuilding Physiology — recovery between bouts.
Sources
- ReviewHotfiel T et al. Advances in delayed-onset muscle soreness (DOMS): Part I: pathogenesis and diagnostics. Sportverletz Sportschaden 2018;32(4):243–250 Published 2018 · DOI 10.1055/a-0753-1884 · Accessed 2026-10-24
- ReviewCheung K, Hume P, Maxwell L. Delayed onset muscle soreness: treatment strategies and performance factors. Sports Med 2003;33(2):145–164 Published 2003 · DOI 10.2165/00007256-200333020-00005 · Accessed 2026-10-24
Corrections (1)
- 2026-10-24 — Re-sourced to dated primary sources (Phase 3 editorial); Review pending. Added Hotfiel et al. 2018 and Cheung et al. 2003 (abstracts read). DOMS timing now cites Hotfiel 2018 (soreness peaks 48–72 h after exercise; primary mechanism is ultrastructural muscle damage from eccentric or unfamiliar exercise, followed by a local inflammatory response). The lactic-acid explanation is labelled as one of the historical theories (Cheung 2003), not the cause of DOMS. The 12–48 h and 24–48 h onset figures are kept as the original reference's wording.
Keep this lesson, or ask how it applies to you.
Educational content only — not medical advice. Always consult a qualified professional for individualized guidance, especially around injury, pregnancy, or medical conditions.