Why Do You Get Sore After a Workout?

Have you ever hit the gym for a serious sweat sesh or started a new physical activity and woken up stiff and in pain the following day? We all experience muscle soreness at some point. It shouldn't startle you, as basic soreness isn't indicative of an injury. It's still frustrating, though. Why do we get sore in the first place?

What Is Muscle Soreness and What Causes It?

The aching sensation after a workout, known as delayed onset muscle soreness (DOMS), is caused by the stress you put on your muscles. During high-intensity exercises, muscle contractions and movements cause microscopic tears along the muscles, muscle fibers, and connective tissues.

The body then reacts to the damage by increasing inflammation. The pain you feel is an effect of the repair process. It begins to occur at least 12 to 24 hours after a workout and can last up to 72 hours.

athlete rubbing sore ankle

DOMS happens when you start a new exercise or when you add a new activity to your current workout program. It also occurs when you increase the intensity of your exercise or when you repetitively perform the same activity without taking sufficient rest time between sets. Essentially, it indicates that you’ve pushed your body to a point that it isn’t used to and caused muscle changes.

You’ll know when you have DOMS when your muscles feel tender to the touch or have a reduced range of motion due to pain and stiffness. Other symptoms include swelling in affected muscles (getting swole), muscle fatigue, and short-term loss of muscle strength.

Muscle soreness can occur after just about any high-intensity workout, but the extent of the pain differs for each person. And there are several factors that explain why:

Training Level and Frequency

Overdoing the duration or intensity of your exercises can lead to sore muscles. Similarly, soreness depends on how often you exercise. When you’re just starting out or you're not used to regular physical activities, your muscle aches will be much worse than those who frequently work out.

woman running up bleachers

This happens because your muscles are trying to get used to new demands or adjusting to the new movements, thus leading to more micro-tears. 

Types of Exercises

Different exercises bring about different results in our bodies. The same goes for the extent of pain you’ll experience afterward. When you lengthen your muscles, like during squats, leg raises, or biceps and triceps extensions during dumbbell workouts, they work harder and get more "damaged" (good damage!) and inflamed.

These eccentric movements cause a muscle to tense at the same time it lengthens, leading to increased soreness afterward. In contrast, concentric movements, like going up steps or using a rowing machine, tend to cause less pain to the muscles.  


    According to research published in the journal Sports Medicine, estrogen, which women have more of than men, stimulates muscle repair and regenerative processes. This means that men tend to experience worse muscle soreness than women, even if they do the same types of exercises at an equal level and frequency.

    So, Is Muscle Soreness a Bad Thing?

    Like we said earlier, muscle soreness doesn't automatically equate to injury. It’s normal and is not something to be alarmed about. It happens to everyone – from beginners to anyone who hasn’t worked out in a long time, to elites, bodybuilders, and even professional athletes.

    man lifting weights at the gym

    It's the body’s natural reaction to strenuous physical activity. It’s a sign that your body is adapting, your fitness is improving, and you’re getting stronger. The pain is part of the adaptation process that results in improved stamina and strength once the micro-torn muscles recover and rebuild.

    When the muscles get used to the physical stress placed upon them, the sore sensation then decreases.

    However, it’s also important to know the difference between DOMS and severe muscle soreness, as the latter can be more damaging and dangerous. You might need to seek medical attention if the pain is too much or if you experience any of the following:

    • Pain during or immediately after you train.
    • Severe, unbearable pain that interferes with your daily activities.
    • Prolonged soreness that lasts more than 72 hours.
    • Swollen arms or legs.
    • Loss of joint motion due to swelling.
    • Dark-colored urine or the inability to urinate.

    How Do You Alleviate Muscle Soreness?

    When your muscles ache, you might be tempted to immediately sit or lie down. However, abruptly stopping your movements and plopping down the couch will just worsen your pain because blood isn’t flowing to your muscles. Try these tips instead to help reduce your soreness. 

    Active Recovery

    Keep your muscles moving by doing low-to-moderate-intensity exercises like walking, light stretching, cycling, swimming, and yoga. You may want to skip the high-intensity cardio or powerlifting exercises when you’re still sore, as these exercises may worsen or delay your recovery. Maximize your recovery by drinking a lot of water, eating the right foods, and getting enough sleep.

    woman stretching upper body


    Get a massage up to 48 hours after your workout to help relieve sore muscles. Target your arms, glutes, calves, shoulders, thighs, or other highly affected areas. If you opt for self-massage, apply oil or lotion to the intended area and knead, squeeze, or shake your muscles gently.

    You can also use a foam roller right after your workout session to help alleviate DOMS.

    Warm Bath

    Dip in a warm tub or take a warm shower to ease the pain of muscle sores. Try a heating pad or a moist heat wrap to minimize the discomfort temporarily.

    Cold Bath

    Taking a post-workout ice bath is found to be better for the muscles in the long run. If that sounds too intense, you can immerse your body in cold water (with a temperature of 50-59*F) for about 10 to 15 minutes to lessen the aches and stiffness brought about by DOMS. 


    Plain Old Rest

    Consider taking a day or two off to reduce the soreness and to avoid the risk of having a serious injury. Sometimes, total rest really is the answer.

    Monitor Which Muscles You Use for Each Workout

    If you make a point of switching up which muscles you target for each workout, you can more easily avoid soreness. But how do you do that? Your Atlas watch will define your muscle activation areas based on the exercises you do. 

    This means you can plan your programming based on which areas haven't been targeted recently. This also helps you monitor your form and ensure you're engaging the correct muscles. 

    At the end of the day, muscle soreness won't hinder you from achieving your health goals. Slowly build up your pace and gradually dial up your intensity so your muscles get to adapt to the impact of your activities.

    If muscle soreness hits you, make sure to address this with the above self-care measures to allow your body to recover properly. In time, DOMS will occur less, your muscles will adapt, and your body will get used to your fitness routine.