Is muscle soreness a sign of a good workout?
No. Soreness mostly tells you a movement was new or eccentric-heavy, not that the workout built muscle. You can grow with zero soreness, and get wrecked by a session that does little for you.
Delayed-onset muscle soreness — that deep ache 24 to 72 hours after training — feels like proof you earned something. It reads like a scoreboard: more sore, better session. The problem is that the thing soreness actually measures isn’t muscle growth.
DOMS shows up when you do something your muscles aren’t used to, especially eccentric (lengthening) work — the lowering half of a curl, running downhill, a movement you haven’t touched in months. It’s a response to novel mechanical stress and the low-grade damage and inflammation that follow. Repeat that same workout a couple of times and the soreness largely vanishes, even as you keep training just as hard. That’s the repeated-bout effect, and it’s the first clue that soreness is tracking unfamiliarity, not effort or results.
The evidence goes further: soreness is a poor gauge of even the damage it gets blamed on. When Nosaka’s group had people do escalating amounts of eccentric work, how sore they felt barely tracked strength loss, swelling, or creatine kinase — the actual damage markers. And damage itself turns out not to be the growth driver people assume. Damas and colleagues found the biggest protein-synthesis spike happens early in a program, right alongside the most damage — and that early response doesn’t correlate with how much muscle you eventually build. Growth only lines up with protein synthesis later, once damage has settled down.
Why the signal is so noisy
Soreness is driven by novelty, eccentric emphasis, connective-tissue involvement, and your own pain sensitivity — none of which map cleanly onto hypertrophy. That’s why a brutal new leg day leaves you limping while well-trained muscles like the delts grow for years with barely a twinge. The muscles you train most consistently — the ones actually growing — are usually the ones that stop getting sore.
What to watch instead
Track the things that actually drive growth: are you adding reps, load, or sets over the weeks, training close enough to failure, and recovering between sessions. Soreness is fine as a rough note that something was new — just don’t use it to score your progress, and don’t chase it.