That soreness you experience after a tough workout often feels like a badge of honor, right? You upped the intensity on leg day or you tacked on a few more miles to your long run and you’re feeling strong. Until one day, you push it too far and that hurts-so-good sensation turns into muscle pain that makes it excruciating to even sit down on the toilet. You’re feeling the burn — but there’s no reason you can’t hit it just as hard tomorrow, right? Not so fast. Sometimes it’s fine to work through mild aches, but here’s how to know when your body might be telling you to back off.
Why Am I So Sore?
Quads on fire after right after squats? That’s pretty normal. The burning sensation you feel mid-workout when you’re fatiguing is the result of lactic acid, says Scott Sailor, President, National Athletic Trainers’ Association. Luckily, “it dissipates out of the muscles pretty quickly,” Sailor says. Lactic acid (sometimes called lactate) will disappear within an hour of exercise. So why can’t you walk down the stairs the next day?
Soreness that develops roughly 12 to 24 hours after a strenuous activity is known as DOMS, delayed onset muscle soreness — and it can last for 24 to 72 hours, according to the American College of Sports Medicine. You can bet your gym socks you’ll experience DOMS any time you perform exercises that are new to you or you complete lots of sets with minimal rest in between, says Neal Pire, MA, CSCS, exercise physiologist at HNH Fitness in Oradell, NJ.
Can I Still Exercise While Sore?
There’s a big difference between mild muscle tenderness and “my glutes are so sore it hurts to sit” pain, which is likely DOMS. (Trust us, you’ll know the difference when you feel it.) Your workouts won’t be nearly as effective if you’re in the throes of major delayed-onset soreness, says Pire. Symptoms include limited mobility and extreme stiffness. “Performance is typically impaired…as you have a loss of muscle strength and power, decrease in range of motion…and localized pain and swelling,” he says.
RELATED: 7 Ways to Relieve Post-Workout Pain
“[DOMS] is not devastating, but there can be an extent where it’s dangerous,” says Sailor. It might seem far-fetched, but being so sore that it’s difficult to make your way down stairs could put you at risk of, well, a face-plant, Sailor points out.
The anti-dote to DOMS? Recovery, and lots of it. If you’re having major trouble walking down the stairs, or getting up from your chair, you may need to recover for three to five days before you start cranking out squats again. Strategies like foam rolling and taking anti-inflammatories (with care) can help alleviate the pain, but they won’t help your muscles on a cellular level, says Sailor. You’re better off Netflix and chilling on the couch instead of hobbling your way through a workout. “Time is your friend,” says Pire. “Rest and let your body recover.”
How Can I Avoid Insane Post-Workout Soreness?
Switching up your routine to target different muscle groups each day is a smart strategy if you like to hit the gym every day of the week. “Evidence shows that two to three resistance training workouts, per muscle group, per week, are ideal,” Pire says. For example, if you’re going to train your legs and glutes twice a week, wait two or three days before challenging them again.
Keep in mind: “We don’t get stronger or more conditioned during workouts,” says Pire. We make much of our progress during recovery, when we allow our bodies to heal and rebuild.
Your best bet: Listen closely to your body and look for these five signs to know when it’s time to take a rest day.
Originally published December 2015. Updated July 2016.