We’ve all been there: You have crushed a tough workout only to be rewarded with stiff, aching muscles the morning after – sometimes 48 hours after. Turns out that uncomfortable feeling, otherwise known as delayed onset muscle soreness (DOMS), is actually a pretty normal side effect of the muscle rebuilding process.
Currently, most think it’s a result of microscopic tears in the muscle and surrounding connective tissue as a result of eccentric exercise. The eccentric phase of a movement occurs when a muscle is lengthening (sometimes referred to as doing “neegatives”). Classic examples would be lowering a dumbbell back to its starting position during bicep curls or running downhill. One thing DOMS doesn’t involve? The build-up of lactic acid, which is actually a common myth. (Lactic acid is gone from your muscles within about an hour after your workout.)
And DOMS isn’t just about soreness. Symptoms can include weakness, stiffness, and sensitivity to touch. The discomfort usually starts to appear within 12 to 24 hours after exercise, peaks after 24 to 72 hours, and should disappear within three to five days.
But here’s the good news. Because the body builds tolerance and adapts pretty rapidly, DOMS should become less frequent if you continue exercising at the same intensity. Enjoy the sore – it means you worked hard and made changes in your muscles.