Is It Safe to Workout When You're Already Sore? We Asked Trainers

We've all been there: It's time for a workout, but your body is sore from a previous day's session. Should you power through your workout, anyway, or is it best to give your body some time to rest? If you're wondering how to navigate muscle soreness, you're far from alone. How long to rest, how to stagger your workouts, and how to tell the difference between soreness and an actual injury can all be tricky to discern.

And when it comes to working out through pre-existing muscle soreness, the answer is a bit more nuanced than a simple yes or no. So to understand when it's safe to exercise through soreness and when you should rest up instead, we tapped asked a sports chiropractor and a personal trainer to divulge everything you need to know. Ahead, learn about the risks, the benefits, and the do's and don'ts of working out while you're already sore.

What Causes Muscle Soreness?

Muscle soreness caused by exercise is also known as "delayed onset muscle soreness,"—a.k.a. the acronym DOMS. "DOMS is predominantly a result of a type one muscle strain following exercise you're not accustomed to," says Dr. Radermacher. "It's minor muscle fiber damage, but nothing serious. It's also caused by the metabolic byproducts of intense exercise, which can cause inflammation of the muscle cell membranes," he adds.

Pierson says that DOMS can be caused by tiny tears in our muscles, the result of our using them in ways beyond how we otherwise would casually in our day-to-day lives. "Muscle soreness occurs because of microtears that happen in the muscles from exercise," she says. "This microtrauma then cues the body’s inflammatory response. As a result, muscle soreness can cause a reduction of range of motion, strength loss, and inflammation," she adds. This type of soreness is nothing to worry about and can be a solid indicator that you've challenged your body in a new way. In fact, the healing process after creating these microtears during exercise is what strengthens and builds muscle.

Benefits of Working Out While Sore

The most important thing is to listen to your body. If it's painful to get through your day-to-day tasks, it's probably best to give your body the rest it needs. That being said, if your soreness is minimal, working out through your soreness can have some recovery benefits.

• Increased Blood Flow: Pierson says that "the main benefit of working out while sore is that it will increase blood flow to the affected area, which will help to decrease the feeling of being sore, even if the relief is only temporary."
• Prevention of Deconditioning: Radermacher tells us that "the problem with totally stopping exercise for an extended period of time is that you decondition your whole body and now you’re in a weaker spot than you were before. And when you’re weaker, you’re more vulnerable to injury once you get back at it again."

Risks of Working Out Sore

As you may be able to guess, the biggest risk of working out while sore is the potential for injury. "The risk of an overuse injury is the most significant risk of working out while sore," Pierson says. "If you want to work out while you are sore, make sure to alter the intensity or muscle groups you target. The bottom line is that your muscles need time to recover," she adds.

If you exercise while sore, expect to perform at a lower caliber than usual. "You won't be able to lift as much or run as long until your muscles are fully recovered," Radermacher says. However, he doesn't think that should fully discourage you from exercise for the duration. "I actually usually recommend that patients keep working out to the best of their ability as long as it doesn't make the pain worse. Instead, rotate muscle groups, keep active and scale back on the reps or weights until the soreness is gone," he recommends.

Soreness vs. Injury

Before deciding whether or not you should work out while you're sore, it's imperative that you be clear that what you're experiencing is regular DOMS, and not an injury. Wondering how to tell? Here are the ways you can discern between the two.

• Immediate and Lengthy Pain: Muscle soreness comes and goes within a few days, but injury hurts immediately after it happens and lasts longer. Radermacher says that "if you exercised three days ago and still can’t move normally, you might be dealing with more than just DOMS. But if it hasn’t yet been 72 hours since you left the gym, you're probably fine—especially if you’re starting a new workout program," Pierson adds. "The pain from an injury starts immediately or within the first 24 hours. With an injury, the pain and other symptoms last much longer than regular muscle soreness. For example, a person with a muscle strain might see bruising, inflammation, sharp pain, or have a decreased range of motion that has a quick onset and lasts longer than a week.
• Sudden, Acute Pain: "DOMS doesn't usually occur until the day or two after a workout," Radermacher says, "so if you're at the gym, make a wrong move and suddenly have pain in your neck, shoulder, wrist, lower back or knee, it's likely you've injured something."
• Swelling Pain, or Pain That Radiates: Radermacher explains that "swelling is a bad sign—it’s part of the body’s natural inflammation process at the site of an injury. Same with radiating pain—it's a sign your nervous system is involved." When in doubt, stop your workouts and see a physician right away if you believe you might be dealing with an injury.

How to Treat and Prevent Soreness

Some degree of muscle soreness is to be expected after your workouts. After all, without microtears in your muscles, there's no repair work to do and your muscles won't strengthen. However, there are ways to mitigate muscle soreness so that you're able to keep your workouts going with as little interruption as possible.

Start Slow

As tempted as you might be to get going quickly when you begin a new workout regime, overdoing it doesn't help anyone, and that should be avoided. "One of the biggest mistakes I see people make is doing too much too soon. Gradually increasing the intensity of your workouts will decrease the amount of soreness you will encounter," informs Pierson. Radermacher agrees, suggesting people "progress slowly into a new workout program, starting with lower volume and working your way up to heavier weights and more sets."

Recover Actively

Active recovery works to help your body send blood to your aching muscles, thus increasing the speed of their repair. Radermacher recommends foam rolling or a vibration massage tool, noting that "foam rolling has been shown to help with post-exercise strength recovery, while vibration therapy with a Theragun or Hypervolt tool can help reduce DOMS-associated pain." Additional choices for active recovery include massage conducted by a person, stretching, yoga, and swimming.

Employ Supplements

There are numerous supplements that can aid with muscle soreness and recovery, and as always, you should consult with your physician before incorporating a new supplement into your routine. Radermacher recommends pre-workout mixes with caffeine because "studies have shown caffeine significantly reduces DOMS symptoms if taken about an hour before a strenuous workout." He also suggests BCAAs (branched-chain amino acids), taurine, and fish oil. "Branch-chain amino acids (BCAAs) help regulate protein synthesis and the repair of muscle tissue. Taurine has been shown to protect cells against the metabolic stress that causes DOMS. Omega-3 fatty acids can minimize DOMS by reducing pro-inflammatory factors," he explains.

The Final Takeaway

When in doubt, listen to your body and give it the rest it needs if you feel too sore to get through another workout (or, you can alternate the muscle group you are working on). Working out while sore can help speed up your recovery and temporarily reduce pain by sending blood to your sore muscles. That said, it does come with risks—the largest one being that you may be more likely to injure yourself due to muscle overuse. There are many differences in the feeling of injury versus soreness, such as how quickly the pain sets in and how long it lasts. You can mitigate muscle soreness by starting slow and utilizing active recovery like foam rolling during your time between workout sessions. Muscle soreness can't be completely avoided, but you can certainly make the most of it.