Today, I want to clear up a common misconception I hear all the time: muscle soreness as the measure of a good workout. You’ve probably thought about it before—“I wasn’t sore after this workout, was it tough enough?” or “I want to feel like I’m dying by the end of the session.” It’s a question I get a lot, and I’ve been guilty of thinking the same way in the past. But the truth is, soreness is probably the least effective way to judge how successful a workout was. So let’s break it down.
First off, let’s go back in time a bit. When muscle soreness was first studied, people blamed lactic acid for the pain. The idea was that lactic acid builds up in the muscles during exercise, causing a burn and disrupting muscle function. But here's the kicker—scientists have been unsuccessful in measuring lactic acid in the body during exercise and appear to be present at all. After some more research, scientists figured out that lactate, not lactic acid, was involved in energy production during exercise. However, lactate isn’t the culprit behind muscle soreness.
So, what is? It’s actually the micro-tearing of muscle fibers that happens when you push your muscles beyond their usual limits. This leads to an inflammatory response in the body, which sends fluid to the area to start the repair process. The muscles rebuild stronger, but this fluid buildup can trigger pressure and pain receptors, leading to that “sore” feeling. But here’s the thing: delayed onset muscle soreness (DOMS) doesn’t always mean you’ve had an effective workout.
The thing that doesn’t add up for me is that DOMS doesn’t usually hit right after the workout—it peaks 24-48 hours later. If micro-tearing was the cause, we’d feel sore immediately, right? But we don’t. This delayed response suggests that the soreness is more about how the body’s immune system responds to the trauma from exercise—specifically the inflammation and fluid buildup around the muscle spindles, which trigger pain signals.
As you get more consistent with training, though, your body adapts. You stop feeling that intense DOMS after every workout because your body gets better at handling the inflammation and doesn’t flood the muscles with as much fluid. This is a good thing, because it means your body is more efficient.
But here’s the kicker: not feeling sore doesn’t mean your workout wasn’t effective. In fact, it’s a sign that your body is adapting and getting stronger. The real indicator of progress is progressive overload—gradually increasing the weight, reps, or sets you’re doing over time. If you’re lifting more weight or doing more reps than you were six months ago, you’re getting stronger, whether or not you’re sore the next day.
So next time you’re concerned about muscle soreness, remind yourself that it’s not the best indicator of a successful workout. Instead, focus on the key principles of progression—more weight, more reps, more sets—and watch your muscle growth and strength follow suit.
Remember, soreness fades as your body adapts. The gains, however, are here to stay. Keep training!