Muscle soreness is about as comfortable as running into your ex in the weight room (which is to say, not at all). And it’s even worse delayed begining muscle soreness (DOMS), which can be even more brutal.
Although they are not exactly same thing (more on that later), muscle soreness and DOMS are often used interchangeably and both refer to muscle tenderness, pain, or stiffness caused by athletic activity. If you’ve ever had a hard time bending over and picking something up after a day’s leg workout, or couldn’t comfortably climb the stairs after a long run, you know firsthand what muscle soreness, or DOMS, feels like. But why do muscles hurt in the first place?
While muscle soreness isn’t generally fun to deal with, there’s a silver lining: It’s often a symptom that you’ve pushed hard enough to make gains, says exercise physiologist and certified strength and conditioning coach Sharon Gamm, PhD, CSCS . However, there is a difference between “good” muscle soreness and muscle soreness that may actually be a problem (ie, an injury). Ahead, exercise pros answer all your questions about muscle soreness, DOMS, and what you can do about it.
Watch this!
Dance FitSugar
What is DOMS? Different types of muscle pain
Commonly abbreviated to DOMs, “delayed-onset muscle soreness refers to pain, tenderness, and/or stiffness in the muscles you’ve exercised after you’ve exercised them,” says Dr. Gam. That first qualifier (“delayed onset”) is there because it’s soreness that doesn’t go away immediately after you’ve exercised, she explains.
To be clear: DOMS is different than your typical muscle soreness. “Both muscle soreness and DOMS have common characteristics, but they differ in timing,” says Rachel Straub, PhD, CSCS, co-author of Injury-Free Weight Training.
Regular muscle soreness can start immediately after physical activity, while DOMS usually takes about 24 hours to appear, says Dr. Straub. Plus, “regular muscle soreness is usually transient and only lasts for hours,” she says, while DOMS can take three to seven days to slowly dissipate and go away. DOMS usually peaks between 24-72 hours after exercise, research shows.
DOMS is also different from the sharp muscle pain you may feel while you’re working out, says Dr. Gamm (think: the burning sensation when you hold a squat or do non-stop core work in Pilates). “When you’re ‘sick’ mid-workout, [that] pain is usually caused by a build-up of lactic acid and hydrogen ions,” she says. Lactic acid is a waste product that the body produces when it converts glucose into energy to fuel your muscles during exercise, she says. “While lactic acid can cause discomfort during exercise, it is cleared from the muscles very quickly after exercise, and it is different from—and does not cause—DOMS.”
Why do muscles hurt?
Simply put, muscles hurt because exercise causes tissue damage, which leads to an inflammatory response, explains Ellen Thompson, head personal trainer at Blink Fitness.
Whether it’s on a treadmill or in the weight room, every time you challenge your muscles beyond their current ability, tiny tears are cut into your muscle fibers and damage is done to the surrounding connective tissues, Dr. Gam explains. Exercise damage may sound like a bad thing, but it’s actually the first and most important step in getting your muscles bigger and stronger. The fact is, when your body repairs the damage, it rebuilds your muscle fibers so they’re even more resilient than they were before, she explains, which means you get stronger and more capable.
These microtears create an inflammatory response in the body, leading to a sensation of pain that registers as muscle soreness, says Dr. Straub. It also prompts your body to increase blood flow to the area to start the healing process.
Blood is rich in oxygen and nutrients that help repair muscle fibers, so blood supply to the area helps speed up recovery. The increased blood flow also speeds up the rate at which metabolites (or “muscle waste”) are carried away from the muscles, Thompson says. This so-called “junk” can increase your feelings of pain and fatigue, according to research, so clearing it can reduce those feelings. Blood flow can also help reduce the stiffness you experience as a result of DOMS, she says.
Which exercises are most likely to cause sore muscles?
DOMS is a likely side effect anytime you are pushing your muscles beyond their current ability. So if you’re doing a higher-intensity workout—whether you’re running (or biking, or rowing) faster, or lifting more weight (or doing more reps)—than your body is used to, DOMS is to be expected. says Dr. Gam.
Eccentric exercises – ie. exercises that focus on lengthening muscles — are also particularly likely to lead to DOMS muscle pain, according to research. Also known as “negative,” eccentric exercises (such as slowly lowering down from the top of a pull-up or push-up) place more stress on the muscle than exercises that focus on contracting the muscle in another way. More stress on the muscles leads to more muscle breakdown, which leaves you sicker.
According to Dr. Gamm, people who are new to exercise are also particularly prone to DOM. That’s because their muscles aren’t trained to exercise, she says, so any physical activity pushes their muscles beyond their current capabilities. This is also why you may feel sore after trying a new type of exercise, even if you are physically active in other ways; the muscles worked by the new workout (say, your upper back while boxing) may not be conditioned by your usual routine (like your quads from running).
That’s exactly why experts recommend that exercisers start new exercise routines with a “slow and steady wins the race” mindset. “If your soreness is consistently greater than 3/10, you are at increased risk of injury because when your body hurts, it may try to protect itself by changing movement patterns,” says Dr. Gam . Also, if you are that sore, you’re less likely to show up to the gym consistently, and consistency is where the real gains are made, she says.
How to deal with sore muscles
When you’re wound up, your sofa can look especially inviting. But actually, Thompson recommends not being a couch potato for the day.
Movement is a lotion, she says, “so relaxing completely for the day can make the pain worse.” Instead, she recommends doing some low-intensity exercise, like going for a walk with hot girls or a light run, taking a yoga class, or doing a mobility flow. Light exercise maintains proper blood flow so your cardiovascular system can deliver nutrients to your muscles and clear away waste products, she explains.
When you’re not moving and moving, you want to give your body what it needs to heal muscle damage quickly, says Dr. Gamm. “The majority of muscle repair and growth happens when you sleep, so getting enough quality sleep is essential,” she says. “Eating high-quality, nutrient-dense foods, including plenty of protein, gives your body the tools it needs to complete the recovery process and heal sore muscles.”
Are muscle aches a good sign? When is soreness a problem?
In most cases, sore muscles are a good sign; it’s just an indication that you’ve challenged your body and it’s working like hell to adapt to the exercise regimen you’re putting it through. That said, you don’t have to be extremely sore to have a good or beneficial workout. You can reap so many of the wonderful health benefits of exercise, such as reducing stress and improving cardiovascular health, even if you’re not sore the next day.
There’s also a difference between productive muscle soreness after a workout and a serious problem. So how can you tell which is which?
For starters, when someone is injured, they can often remember a specific “moment” while exercising that marked the onset of pain, Dr. Straub says. “If you experience a sudden, sharp pain that feels unusual when you exercise, or hear a popping sound, chances are you’ve suffered a severe injury.” However, common muscle soreness is rarely marked by a single auditory or sensory moment, but rather increases with passage of time and always after you’re done training.
Also, “when a person has a serious muscle injury that requires medical attention — such as a muscle strain or stress fracture — the underlying pain does not subside or improve within a few days,” says Dr. Straub. Rather, the pain either stays the same or gets worse. If you’re still sore five or more days after a workout, it’s a sign you may have a hand injury.
In addition to the duration of the pain, the intensity of the pain can also help you infer whether the muscle soreness is something more concerning. DOMS is often characterized by generalized muscle fatigue and joint stiffness, Thompson says. Your muscles may even be tender to the touch, she says. “A disease that can be described as sharp, shooting, or throbbing, or is accompanied by intense swelling and throbbing, is also likely to be an injury.”
And in very rare cases, excessive exercise that causes significant muscle damage can lead to kidney failure and a life-threatening condition called rhabdomyolysis. Common signs of the condition are weak muscles, muscle stiffness, muscle pain and a change in the color of your urine, according to the Cleveland Clinic. If you have excessive muscle pain, muscle swelling, or dark urine, consult your doctor immediately.
In general, if you’re not sure whether your muscle pain is a simple case of DOMS or something more serious, see your physical therapist or other health care provider. They will be able to run through some basic tests to determine the cause of your pain and suggest next steps for healing if needed.