Does Muscle Soreness Mean Muscle Growth?

Two days after a heavy leg session, the stairs become a negotiation. For many lifters that ache is worn like a badge, treated as proof the muscle was worked hard enough to grow. It is one of the most persistent beliefs in the gym, and one of the least supported by the evidence.

Delayed onset muscle soreness, or DOMS, is real, measurable, and well studied. What it is not is a reliable readout of how much muscle you built. The research over the past decade has steadily separated the sensation of soreness from the adaptations that actually drive hypertrophy and strength, and the gap between the two is wider than most training culture assumes.

What DOMS actually is

DOMS is the muscle pain and stiffness that peaks roughly 24 to 72 hours after an unfamiliar or strenuous bout of exercise. It is driven primarily by mechanical strain on muscle fibres and connective tissue, especially under lengthening (eccentric) contractions, followed by a local inflammatory and repair response. The old story about lactic acid causing soreness has long been discarded; lactate clears within an hour of finishing a set and has nothing to do with pain felt two days later.

The key word is unfamiliar. Soreness is largely a novelty response. A new exercise, a longer range of motion, more eccentric loading, or simply more volume than your tissue is used to will all provoke it. The repeated bout effect describes how quickly the body adapts: a single exposure to a damaging session confers substantial protection against the next one, blunting soreness, creatine kinase release, and force loss on subsequent bouts.¹,² This protective adaptation appears to involve a form of cellular memory in the muscle, building remodelled, more resilient tissue rather than signalling that the first session was somehow inadequate.³

Soreness is not a measure of muscle growth

The most direct evidence comes from work tracking muscle protein synthesis, the molecular signal underpinning growth, alongside markers of muscle damage across a training programme. In untrained lifters, the early rise in myofibrillar protein synthesis after the first sessions is inflated by, and directed toward, repairing damage. It correlates with how sore and damaged the muscle is, not with how much it will eventually grow. Only once the damage response is attenuated, several weeks into training, does the protein synthesis signal begin to track actual hypertrophy.⁴ In other words, early soreness reflects repair, not construction.

Reviewing the broader picture, the same group concluded that muscle damage is not the mechanism that mediates or potentiates resistance-training hypertrophy. Protocols that produce minimal damage generate comparable size and strength gains to those causing significant initial damage.⁵ The primary driver of growth is mechanical tension sensed by the muscle fibre and the signalling cascades it triggers, not the collateral damage that happens to accompany unfamiliar training.⁶

This is why experienced lifters keep progressing for years while rarely feeling deeply sore. Their tissue has adapted. The absence of soreness is not a sign that training has stopped working; it is a sign that the protective adaptations are doing exactly what they should.

Why chasing soreness backfires

If soreness were merely an unreliable signal, it would be harmless. The problem is that training to maximise it can actively work against your goals. Taking every set to momentary failure, for example, reliably increases neuromuscular fatigue, muscle damage, and perceived discomfort, yet a scoping review of proximity-to-failure found that training to failure is likely not superior to stopping short for hypertrophy.⁷ You pay a real recovery cost in soreness and fatigue, and buy no extra growth with it. That extra fatigue can even reduce the quality and volume of your subsequent sessions, quietly lowering the total productive work you accumulate over a week.

The dissociation runs in the other direction too. Recovery interventions can strip away soreness without touching the underlying adaptation, and in some cases can blunt it. Branched-chain amino acid supplementation measurably reduces post-exercise soreness and damage markers without any claim to enhanced muscle growth.⁸ Hydrotherapy and cryotherapy modalities reliably lower soreness after damaging sessions.⁹ Yet routine cold water immersion after resistance training, while it dampens soreness, has been shown to attenuate the hypertrophic response over time.¹⁰ Soreness and growth are simply not the same variable, and treating one as a proxy for the other leads to poor decisions in both directions.

What soreness can usefully tell you

None of this means soreness is meaningless. It carries information, just not the information most lifters assign to it. Marked soreness is a useful flag for novelty and for accumulated mechanical strain: a new movement, a sharp jump in volume, or a return after time off. It is a reasonable cue to manage load progression and recovery, particularly because the soreness and recovery response varies considerably between individuals and tends to be slower in older trainees.¹¹

What soreness cannot do is rank your sessions by how productive they were. A session can be highly effective with little soreness, and a session can leave you wrecked while delivering nothing extra for hypertrophy. In trained athletes, adaptation tracks the load and intensity that was actually completed, not the ache that follows.¹² The signal that matters is whether the target muscle was sufficiently loaded through a meaningful range, with enough quality reps, accumulated across the week. Soreness is, at best, a noisy and lagging shadow of that.

What this means in practice

The practical shift is to stop using soreness as a scorecard and start judging sessions by stimulus. Concretely:

• Do not add volume or intensity simply because you are not sore. Adaptation, not soreness, is the goal, and a well-adapted muscle is supposed to feel less sore over time.²,⁵

• Do not interpret heavy soreness as a productive session. It usually reflects novelty or excess damage, both of which carry a recovery cost without a growth bonus.⁴,⁷

• Progress load and reps deliberately over weeks, rather than reaching for whatever leaves you most wrecked the next day.

• Treat a sudden spike in soreness as a cue to check that volume or exercise selection has not jumped too far, too fast.¹¹

This is precisely where direct measurement changes the conversation. Instead of inferring effort from how you feel two days later, a muscle-sensing wearable reads the working muscle during the set itself: how strongly it was recruited, how its output held or faded across reps, and how that compares with your previous sessions. That surfaces the variable that actually drives growth, the stimulus delivered to the target muscle, rather than the soreness that arrives late and means something else. Training to a clear signal of stimulus, instead of training to soreness, is the difference between guessing and knowing whether a set counted.

Key takeaways

• DOMS is driven by mechanical strain and the subsequent repair response, peaks 24 to 72 hours later, and is mostly a novelty signal. It is not caused by lactic acid.

• Early post-training protein synthesis is directed toward repairing damage and correlates with soreness, not with the hypertrophy that follows once damage subsides.⁴,⁵

• Mechanical tension, not muscle damage, is the primary driver of growth, and low-damage protocols build muscle just as well.⁵,⁶

• Chasing soreness, including taking every set to failure, adds fatigue and recovery cost without adding growth.⁷

• Judge a session by the stimulus delivered to the target muscle, not by how sore you feel afterwards.

References

1. Boyd, L., Deakin, G. B., Devantier-Thomas, B., Singh, U., & Doma, K. (2023). The effects of pre-conditioning on exercise-induced muscle damage: A systematic review and meta-analysis. Sports Medicine, 53(8), 1537–1557.

2. Doma, K., Matoso, B., Protzen, G., Singh, U., & Boullosa, D. (2023). The repeated bout effect of multiarticular exercises on muscle damage markers and physical performances: A systematic review and meta-analyses. Journal of Strength and Conditioning Research, 37(12), 2476–2487.

3. Calvo-Rubio, M., Garcia-Dominguez, E., Tamayo-Torres, E., Soto-Rodriguez, S., Olaso-Gonzalez, G., Ferrucci, L., de Cabo, R., & Gomez-Cabrera, M. C. (2024). The repeated bout effect evokes the training-induced skeletal muscle cellular memory. Free Radical Biology and Medicine, 224, 247–254.

4. Damas, F., Phillips, S. M., Libardi, C. A., Vechin, F. C., Lixandrao, M. E., Jannig, P. R., Costa, L. A. R., Bacurau, A. V., Snijders, T., Parise, G., Tricoli, V., Roschel, H., & Ugrinowitsch, C. (2016). Resistance training-induced changes in integrated myofibrillar protein synthesis are related to hypertrophy only after attenuation of muscle damage. The Journal of Physiology, 594(18), 5209–5222.

5. Damas, F., Libardi, C. A., & Ugrinowitsch, C. (2018). The development of skeletal muscle hypertrophy through resistance training: The role of muscle damage and muscle protein synthesis. European Journal of Applied Physiology, 118(3), 485–500.

6. Wackerhage, H., Schoenfeld, B. J., Hamilton, D. L., Lehti, M., & Hulmi, J. J. (2019). Stimuli and sensors that initiate skeletal muscle hypertrophy following resistance exercise. Journal of Applied Physiology, 126(1), 30–43.

7. Refalo, M. C., Helms, E. R., Hamilton, D. L., & Fyfe, J. J. (2022). Towards an improved understanding of proximity-to-failure in resistance training and its influence on skeletal muscle hypertrophy, neuromuscular fatigue, muscle damage, and perceived discomfort: A scoping review. Journal of Sports Sciences, 40(12), 1369–1391.

8. Salem, A., Trabelsi, K., Jahrami, H., AlRasheed, M. M., Boukhris, O., Puce, L., Bragazzi, N. L., Ammar, A., Glenn, J. M., & Chtourou, H. (2024). Attenuating muscle damage biomarkers and muscle soreness after exercise-induced muscle damage with branched-chain amino acid supplementation: A systematic review and meta-analysis. Sports Medicine - Open, 10, 42.

9. Chen, R., Wang, J., Wu, X., & Li, Y. (2024). The effects of hydrotherapy and cryotherapy on recovery from acute post-exercise induced muscle damage: A network meta-analysis. BMC Musculoskeletal Disorders, 25, 749.

10. Petersen, A. C., & Fyfe, J. J. (2021). Post-exercise cold water immersion effects on physiological adaptations to resistance training and the underlying mechanisms in skeletal muscle: A narrative review. Frontiers in Sports and Active Living, 3, 660291.

11. Hayes, E. J., Stevenson, E., & Sayer, A. A. (2023). Recovery from resistance exercise in older adults: A systematic scoping review. Sports Medicine - Open, 9, 51.

12. McQuilliam, S. J., Clark, D. R., Erskine, R. M., & Brownlee, T. E. (2023). The effect of high- versus moderate-intensity resistance training on strength, power, and muscle soreness in male academy soccer players. Journal of Strength and Conditioning Research, 37(6), 1250–1257.