Does muscle soreness mean your muscles grew?

No. Delayed onset muscle soreness (DOMS) mostly tells you that a workout was new to you or had a lot of hard lowering, and it says little about how much muscle you built. In a 10-week leg study, soreness two days after the first session scored 61 out of 100 and about 8 by week 3, yet the muscle fibers only grew later, about 14 % by week 10, and soreness didn’t predict who grew most (Damas et al. 2016b). Some soreness when you start a program is normal, and you don’t need it to grow.

What DOMS is and why it happens

DOMS is the tender, stiff ache that starts about 6–8 hours after a hard workout and peaks around 48 hours (Schoenfeld & Contreras 2013). It hurts most when you press on the muscle, stretch it or use it, and it fades over a few days.

Three things make it likely:

• Lowering a weight under control (eccentric work), especially with the muscle stretched. The leading explanation is that the weakest sarcomeres, the muscle’s smallest contractile units, get pulled past the point where they can hold on, and some are pulled apart (Proske & Morgan 2001)
• A new exercise, or a muscle you haven’t trained for a while, as when you return after a break (Cheung et al. 2003)
• A lot of hard work for that muscle in one session (Cheung et al. 2003)

Endurance exercise can cause it too. Marathon runners get very sore legs without building much muscle, which is one reason soreness alone can’t stand for growth (Schoenfeld & Contreras 2013).

Does soreness track muscle growth?

Not well. Soreness doesn’t even track muscle damage closely, and damage in turn doesn’t track growth. These studies tested each link:

Study	Who and what	Soreness or damage	Growth
Nosaka et al. 2002	110 men, 12, 24 or 60 maximal lowerings of the arm	24 and 60 lowerings did more damage than 12, but soreness on pressing and flexing was about the same	Not measured
Flann et al. 2011	Eccentric cycling for 8 weeks, one group eased in over 3 weeks first	The group that started cold had over 5 times the creatine kinase (a damage marker) and more soreness	Same muscle growth in both groups, and strength +25 % against +26 %
Damas et al. 2016b	10 men, leg press and leg extension twice a week for 10 weeks	Soreness 61/100 in week 1, about 8 in weeks 3 and 10, and damage seen under the microscope fell too	Fibers grew about 14 % by week 10. Soreness, strength loss and creatine kinase didn’t correlate with growth

In the Damas study, muscle protein synthesis after the first session was high but didn’t relate to growth. It went to repair. Only the responses at weeks 3 and 10, once damage had faded, correlated with how much each man grew. The same group found that much of the extra muscle size you can measure in the first three weeks is swelling (Damas et al. 2016a). The authors’ own review concludes that damage doesn’t drive growth, and that programs causing little damage build about as much muscle as programs causing a lot (Damas et al. 2018).

Where the evidence stops: these studies are small and mostly in people new to the exercise. An earlier review left room for some damage adding to growth, while warning against chasing high soreness (Schoenfeld & Contreras 2013). No trial has made trained lifters more or less sore with the same training and followed their growth for months.

Why soreness fades while you keep growing

One hard session protects a muscle against damage and soreness from the same kind of work, an adaptation called the repeated bout effect. A second bout a week later leaves the muscle much less sore and stiff (Proske & Morgan 2001). After one bout of hard arm lowerings, the protection lasted at least 6 months and was gone by 9 to 12 (Nosaka et al. 2001). It seems to come from several changes at once, in the nervous system, the muscle’s mechanics and the connective tissue around the fibers (Hyldahl et al. 2017).

Muscles also differ. Some lifters rarely get sore in certain muscles that are well developed anyway (Schoenfeld & Contreras 2013). If you train each muscle often with the same exercises, you’ll seldom be sore, and that is no sign of a wasted program.

To judge growth, track what you can count. More reps or more weight on the same exercise at the same effort, week after week, show that the muscle is getting stronger (see progressive overload, week by week). Enough hard sets per week matter more than how a session feels the next day (see how many sets per muscle per week).

Should you train a sore muscle?

Usually you can. In one experiment, 12 untrained men repeated a damaging bout of arm lowerings 3 and 6 days after the first, before the muscle had recovered. The extra bouts didn’t add damage or slow recovery (Nosaka & Clarkson 1995). What does suffer is performance. In the Damas study, leg strength was about 22 % below normal for two days after the first session (Damas et al. 2016b). A sore muscle lifts less, and pain can change how you move (Schoenfeld & Contreras 2013).

A sports medicine review suggests easing intensity and volume for a day or two after a very sore session, or training other muscles meanwhile (Cheung et al. 2003). Our practical reading, which no study has tested as a rule: if you’re mildly sore and your warm-up sets feel normal, train as planned. If you’re still sore enough that you can’t match last week’s reps, or the soreness changes how you move, give that muscle another day or a lighter session.

What reduces soreness, and what can cost you muscle

The most reliable fix is to avoid big jumps in the first place. Bring in a new exercise, or come back after a break, gradually over a week or two, with fewer and easier sets at first (Cheung et al. 2003). In the eased-in group of Flann et al. 2011, that avoided the soreness and cost no growth.

A meta-analysis that pooled 80 studies of DOMS ranked recovery methods by how much they reduced it (Dupuy et al. 2018):

Method	Effect on soreness
Massage	Largest reduction
Light exercise, compression garments	Moderate to large reduction
Cryotherapy, water immersion, contrast baths	Smaller reduction
Electrical stimulation, stretching, hyperbaric oxygen	No clear effect

Two of the things people take for soreness may cost muscle when used every session:

• Cold water immersion: 21 active men who sat in cold water for 10 minutes after each of their twice-weekly sessions for 12 weeks gained less strength and muscle than men who did 10 minutes of easy active recovery instead (Roberts et al. 2015)
• High doses of ibuprofen: young adults who took 1,200 mg every day for 8 weeks of leg training grew their quadriceps about half as much (3.7 % against 7.5 %) as those on low-dose aspirin (Lilja et al. 2018)

Neither study tells you about an occasional ice bath or one painkiller. They tested daily or every-session use. For medication questions, ask your doctor or pharmacist.

When soreness is a warning sign

Rarely, very hard or very unfamiliar exercise breaks down so much muscle that its contents flood the blood, a condition called exertional rhabdomyolysis. It is more common in beginners, after huge numbers of eccentric reps, in heat and with dehydration, and with some drugs and supplements. Its early signs look like ordinary DOMS, which is why it gets missed (Kim et al. 2016).

See a doctor promptly if, after a workout, you have:

• Dark, tea- or cola-colored urine
• Muscle pain or swelling far beyond anything you’ve felt after training before
• Severe weakness, or nausea, vomiting or fever along with the pain

Pain in a joint or a tendon is a different signal. Soreness spreads through the belly of the muscle, comes on the next day and eases within days. Sharp pain at a joint, or pain that appears during a set and in a single spot, deserves a change of exercise and, if it persists, a professional’s look.

How Workout Wizard does it

When you start a muscle’s first exercise in a session, Workout Wizard can ask how sore that muscle got after you last trained it: never sore, healed well before today, healed in time, or still sore. Once you finish the muscle’s exercises, it asks about the pump and the workload. Those three answers decide how many sets the muscle gets the next week. Joint pain is a separate question for each exercise.

The app uses soreness as a sign of recovery, which is a different question from growth. It asks when the soreness ended compared with the next session, that is, whether the muscle was ready to train again. The studies above show that how sore you get says little about how much you grow. A muscle that is still sore at its next session is also weaker for now, as the Damas study showed, and that bears on how much work it can do that day.

None of the studies above tested this exact scheme. It is one structured way to let each muscle’s recovery guide its sets.

Should you judge a workout by how sore you are?

No. Expect soreness when something is new, and expect it to fade as you keep training. Judge your program by the reps and weight you add over the weeks, train through mild soreness, and back off when it stops you from matching last week’s numbers.

References

• Cheung K, Hume P, Maxwell L. 2003. Delayed onset muscle soreness: treatment strategies and performance factors. Sports Med 33(2):145–164. doi:10.2165/00007256-200333020-00005. PMID 12617692.
• Damas F et al. 2016a. Early resistance training-induced increases in muscle cross-sectional area are concomitant with edema-induced muscle swelling. Eur J Appl Physiol 116(1):49–56. doi:10.1007/s00421-015-3243-4. PMID 26280652.
• Damas F et al. 2016b. Resistance training-induced changes in integrated myofibrillar protein synthesis are related to hypertrophy only after attenuation of muscle damage. J Physiol 594(18):5209–5222. doi:10.1113/JP272472. PMID 27219125.
• Damas F, Libardi CA, Ugrinowitsch C. 2018. The development of skeletal muscle hypertrophy through resistance training: the role of muscle damage and muscle protein synthesis. Eur J Appl Physiol 118(3):485–500. doi:10.1007/s00421-017-3792-9. PMID 29282529.
• Dupuy O et al. 2018. An evidence-based approach for choosing post-exercise recovery techniques to reduce markers of muscle damage, soreness, fatigue, and inflammation: a systematic review with meta-analysis. Front Physiol 9:403. doi:10.3389/fphys.2018.00403. PMID 29755363.
• Flann KL et al. 2011. Muscle damage and muscle remodeling: no pain, no gain? J Exp Biol 214(4):674–679. doi:10.1242/jeb.050112. PMID 21270317.
• Hyldahl RD, Chen TC, Nosaka K. 2017. Mechanisms and mediators of the skeletal muscle repeated bout effect. Exerc Sport Sci Rev 45(1):24–33. doi:10.1249/JES.0000000000000095. PMID 27782911.
• Kim J et al. 2016. Exercise-induced rhabdomyolysis mechanisms and prevention: a literature review. J Sport Health Sci 5(3):324–333. doi:10.1016/j.jshs.2015.01.012. PMID 30356493.
• Lilja M et al. 2018. High doses of anti-inflammatory drugs compromise muscle strength and hypertrophic adaptations to resistance training in young adults. Acta Physiol 222(2):e12948. doi:10.1111/apha.12948. PMID 28834248.
• Nosaka K, Clarkson PM. 1995. Muscle damage following repeated bouts of high force eccentric exercise. Med Sci Sports Exerc 27(9):1263–1269. doi:10.1249/00005768-199509000-00005. PMID 8531624.
• Nosaka K, Newton M, Sacco P. 2002. Delayed-onset muscle soreness does not reflect the magnitude of eccentric exercise-induced muscle damage. Scand J Med Sci Sports 12(6):337–346. doi:10.1034/j.1600-0838.2002.10178.x. PMID 12453160.
• Nosaka K, Sakamoto K, Newton M, Sacco P. 2001. How long does the protective effect on eccentric exercise-induced muscle damage last? Med Sci Sports Exerc 33(9):1490–1495. doi:10.1097/00005768-200109000-00011. PMID 11528337.
• Proske U, Morgan DL. 2001. Muscle damage from eccentric exercise: mechanism, mechanical signs, adaptation and clinical applications. J Physiol 537(2):333–345. doi:10.1111/j.1469-7793.2001.00333.x. PMID 11731568.
• Roberts LA et al. 2015. Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. J Physiol 593(18):4285–4301. doi:10.1113/JP270570. PMID 26174323.
• Schoenfeld BJ, Contreras B. 2013. Is postexercise muscle soreness a valid indicator of muscular adaptations? Strength Cond J 35(5):16–21. doi:10.1519/SSC.0b013e3182a61820. Not indexed in PubMed.