• To get rid of sore muscles, you should rest and ice the muscles, try foam rolling, and make sure to drink lots of water.
• Delayed onset muscle soreness is a part of building muscle — when you work out, small muscle tears occur, resulting in next-day soreness — and once you let those muscles recover, they end up stronger.
• Acute muscle soreness occurs during exercise that is too intense or performed with poor form, and this is not helpful to your muscles and can cause injury.
• This article was medically reviewed by Boleslav Kosharskyy, MD, associate medical director of pain medicine for the Joint Replacement Center at Montefiore Medical Center.
• Visit Insider's homepage for more stories.

Sore muscles can occur any time you exercise in a new way that your body isn't used to, or when you increase the intensity of your usual workouts.

Here's what you need to know about why your muscles feel sore and how to relieve soreness.

Why do muscles get sore?

There are two types of muscle soreness: acute and delayed onset.

Acute muscle soreness happens during the activity — say if the exercise is too intense or you're using bad form — and is an indication you should stop immediately because it could lead to muscle or joint damage, according to the American College of Sports Medicine (ACSM).

Delayed onset muscle soreness (DOMS), on the other hand, sets in about 12 to 24 hours after exercise. It's why you feel so sore the morning after a workout. These sore muscles usually last one to three days, though it can take up to 10 days for soreness to resolve completely. And while DOMS may hurt, it can be helpful for muscle repair.

As you're working out, your muscle fibers may tear slightly. Those tiny muscle tears lead to hypertrophy, which means the muscle cells get bigger, says Julia Iafrate, DO, an assistant professor of rehabilitation and regenerative medicine at Columbia University Medical Center. Once you let the muscle fibers recover, the muscle ends up stronger than it was before.

Just make sure you don't work out those muscles before they're done healing — trying to perform intense exercise on sore muscles can result in further pain or even injury.

How to get rid of sore muscles

While there's no way to speed up the body's muscle repair process, you can treat or reduce the symptoms of soreness in a few ways:

• Applying ice to the muscle. Applying a ThermaCare cold wrap to the muscle immediately after exercise or 24 hours later helped reduce pain, according to a 2015 study published in the Journal of Strength and Conditioning Research. Iafrate suggests combining cold therapy with massage: for example, she recommends freezing a Dixie cup of water, removing the paper cup once frozen, and massaging the muscle with the ice for five to 10 minutes.
• Foam rolling. This involves massaging a muscle on top of a foam roller in order to relieve muscle tightness. When it's done post-exercise, it decreases muscle pain and improves muscle strength recovery, according to a 2020 study published in the Journal of Athletic Training. For best results, Iafrate recommends foam rolling after all of your usual workouts.
• Resting the sore muscles. Iafrate recommends mixing up the muscle groups you work and giving sore muscles a chance to completely recover before exercising them again. "Light activity is totally fine — you just need to change up the muscle groups you're working so you give the muscles time to rest a little bit and rehabilitate on their own and heal before they get stressed again," Iafrate says.
• Staying hydrated. According to a 2005 study published in Journal of Athletic Training that involved working out in 104-degree heat, dehydrated study participants reported nearly 7% higher pain scores in their quadriceps 24 and 48 hours post-exercise compared to study participants who stayed hydrated. And while you probably won't be working out at such high temperatures, the downsides of dehydration carry over — if you want quicker muscle recovery, it's important to drink lots of water.
• Drinking coffee before the workout. A 2013 study published in the Journal of Strength and Conditioning Research found that ingesting 5 milligrams of caffeine per kilogram of body weight immediately before a workout led to less muscle soreness two and three days later. That's the equivalent of about one to two 8-ounce cups of coffee for someone who is 150 pounds. Just make sure you don't get too jittery from the caffeine — some trainers recommend green or black tea if coffee doesn't sit right with you.
• Trying acupuncture. A 2020 study published in the Journal of Bodywork and Movement Therapy found acupuncture after a workout can reduce acute muscle soreness by half and DOMS by one-third.

You may also be tempted to pop an anti-inflammatory medication — like Advil or Aleve — until the soreness subsides, but Iafrate warns this could delay muscle repair.

"If the inflammation is too much to bear, then sure, take an Aleve, but it's not something you want to do continuously," she says. "You actually need that inflammation in order to heal."

When to see your doctor for muscle soreness

Run-of-the-mill soreness doesn't warrant a doctor's visit. "But there's a fine line of what's too much soreness," Iafrate says.

Soreness can feel achy, while a muscle strain, which is more serious, may be accompanied by swelling, bruising, and pain, according to Harvard Health.

Iafrate says if your soreness lasts longer than a week, it could indicate something concerning. As long as you have a safe workout regimen, the risk is low for these conditions, but they may occur:

• Ruptured muscle or tendon. Iafrate says that this will be accompanied by severe pain, out of proportion to what you're accustomed to, and inability for the muscle to function.
• Muscle contusion. This presents as a bruise, but it can cause deep tissue damage if it's severe, according to the American Academy of Orthopaedic Surgeons.

You'll also want to take debilitating pain, swollen limbs, or darker-than-normal urine as a sign to seek medical attention, according to the ACSM. Iafrate suggests seeing a primary care physician or a sports medicine specialist if you're concerned about muscle pain.

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• How to use resistance bands to tone your entire body without ever going to the gym
• Which exercises help sculpt your abs, and how to do them at home
• How to do suspension training exercises at home to get a full-body workout

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