Sore muscles from exercise

Sore Muscles From Exercise? Here’s What You Need To Know

Waking up feeling sore the day after a workout? Sore muscles can occur after most workouts. However, it is important to understand muscle soreness that’s derived from workouts; and not muscle pain or discomfort. 

Here’s why muscle soreness can occur from workouts, and what you can do about it. 

What is muscle soreness?

Muscle soreness is a common symptom that follows many workouts, especially if those workouts are at a higher intensity than your muscles are used to or if you performed challenging resistance-training exercises. Muscle soreness from exercise can leave your muscles feeling tight or achy as they recover and repair from the physical exertion of your workout. 

What kinds of muscle soreness are there?

Acute soreness

Acute muscle soreness can start while you’re still working out and can last for a couple of hours after your workout has finished. 

Delayed onset muscle soreness.

On the other hand, delayed onset muscle, soreness (DOMS) tends to start anywhere from 24-48 hours after your workout is over. DOMS can also persist for a couple of days. 

Why are my muscles so sore after exercise? 

Delayed onset muscle soreness isn’t caused by a build-up of lactic acid. 

It’s a common myth that sore muscles the day after your workout are caused by a buildup of lactic acid. As you work out, your muscles use stored carbohydrates for energy, and lactic acid is created as a result. Many people are under the misconception that lactic acid causes soreness, but this isn’t actually right.

A buildup of lactic acid can cause muscle fatigue during an exercise, which can lend itself to the acute “burn” you might feel while you’re working out. But lactic acid also leaves your system pretty quickly and doesn’t seem to play a role in the soreness you feel in the days following your workout. 

Instead, researchers believe that delayed onset muscle soreness stems from a combination of physical and neurological factors. 

On the physical side is muscle damage. Certain workouts damage your muscles on a microscopic level. When you’re working out your muscles are under a ton of stress, which can cause little “microtears” on the muscle fibers. While this might sound scary, what this actually means is that your muscles can then become repaired with the right recovery and nutrition, leading to bigger, stronger muscles over time. Unfortunately, one of the side effects of this microscopic damage to your muscle fibers is that you may experience some pain and inflammation after your workout as your body heals, thus leading to delayed onset muscle soreness in the following days. 

Virtually any kind of exercise can cause this microscopic damage when you’re pushing your muscles harder than they are used to. However, DOMS is especially common when you’re doing eccentric exercises. Eccentric exercises require you to lengthen your muscle under tension and are common in a variety of high-intensity exercises. Take running, for example. Both your hamstrings and your quadriceps go through eccentric movements while you’re running, which allows you to control your stride and provides power to push and pull your body forward.

But in addition to that physical muscle damage that comes from a workout, there are also neurological factors that can lead to post-workout muscle pain and soreness. Researchers now know that some of the pain and soreness from delayed onset muscle soreness is driven by hyperactive motor neurons, the specialized brain cells that signal for our muscles to contract and move. During intense exercises, hyperactive motor neurons can “fire” off excessively into your fatiguing muscles at an accelerated and uncontrolled rate. Unfortunately, the constant pounding of the muscle by those hyperactive motor neurons can also contribute to that lingering soreness in the following days. 

By addressing both the physical and the neurological roots of muscle soreness, you’ll be better able to optimize your muscle recovery and minimize the subsequent pain that may come with the process. 

What do sore muscles from exercise feel like? 

Wondering if the pain you’re feeling after your workout is normal? Common signs of muscle soreness after a workout include: 

  • Dull pain
  • Tenderness
  • Stiffness 
  • Swelling 
  • Temporarily reduced strength 

How long do sore muscles usually last? 

According to the American Council of Exercise, delayed onset muscle soreness generally starts about 24-48 hours after your workout is over and starts declining after about 72 hours. 

Should I still exercise if my muscles are sore?

The pain and stiffness you’re feeling after a workout might be a deterrent to working out again any time soon. But as long as the pain isn’t too severe or debilitating, delayed onset muscle soreness is not a serious condition, and it doesn’t necessarily mean that you need to stop exercising.

However, you may want to take it a little easier and do a more low-impact workout the next day as you recover. For example, you might try swimming a couple of laps in the pool instead of performing high-intensity sprints or working on a lower-resistance bodyweight circuit instead of hitting the weights. You might also consider training a different muscle group if one area of your body is particularly sore (for example, training legs while your upper body is sore and in recovery). 

When to be concerned about muscle soreness

Sore muscles after a workout are fairly common, but how do you know what’s normal and what’s not? To ensure that you’re not dealing with an injury, you should talk to your doctor if: 

  • Soreness and pain last longer than a week 
  • Your soreness is severe enough to actively get in the way of your daily routine 
  • Your pain is sharp and concentrated 
  • Pain management (like icing, rest, and painkillers) aren’t working 

Additionally, if you haven’t been working out but are dealing with a case of sore muscles, it could be a sign that there’s something else going on. Other causes of sore muscles besides exercise include strain injuries, chronic fatigue syndrome, fibromyalgia, rheumatoid arthritis, and more. Speak to your doctor if you’re dealing with unexplained pain. 

How can you prevent muscle soreness from an exercise workout?

Some evidence-based ways to prevent excessive muscle soreness from your workout: 

Warm up before your workout

Before diving headfirst into your intense workout session, make sure you’re giving your body ample time to “warm-up” and get your muscles ready first. Studies have found that warming up with a lower-impact aerobic activity before a workout can increase blood flow to your muscles and slowly bring your metabolism up to speed, which translates to increased range of motion and a subsequent decrease in pain in the following days. 

Progressive overload

Advancing your fitness and making progress towards your fitness goals requires doing consistent and challenging workouts. But working your muscles hard and too quickly can lead to more muscle damage, and that’s not necessarily a good thing since it can increase your risk of soreness and even injury. Start any new workout program slowly and steadily to get your muscles used to the movement and prevent serious muscle damage. 

Prioritizing good nutrition

You should be paying just as much attention to your diet as your workout routine so that your body can recover properly from all that physical stress and damage. Pay special attention to your protein and carbohydrate intake to ensure that you’re giving your muscles all the refueling power that they need.

Staying hydrated

Dehydration during your workout can lead to excess muscle damage, which can then translate to more soreness after the fact. Make sure you’re drinking plenty of water before, during, and after your workout to keep your muscles well-hydrated. This applies whenever you’re working out, but especially if you’re sweating hard! 

Calming hyperactive nerves 

Because research is now showing that hyperactive motor neurons can contribute to DOMS, addressing the neurological factors in addition to the physical muscle damage may also help minimize the pain and speed up your recovery after a big workout. Using HOTSHOT For Muscle Soreness before or after your workout can proactively tackle DOMS by inhibiting the excess, repetitive firing by those hyperactive motor neurons during a workout, stopping cramps and reducing muscle soreness the next day. 

Key Takeaways 

Sore muscles are fairly common after workouts, but they can still be uncomfortable and even concerning if you aren’t used to the feeling. The good news is that mild delayed onset muscle soreness is a side effect of the repair process your body goes through to repair the damage that your muscles experience after a workout. It’s all a part of the process that allows them to grow! Take care of your body by prioritizing recovery and nutrition to minimize the pain and reap the rewards of your exercise routine. 

Featured image credit: Photo by Andrea Piacquadio from Pexels

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