Workout Wednesday: Why Are My Muscles So Darn Sore After That Workout?

Last week, after returning to the SRC from a solid month of no gym access that caused me to rely on bodyweight exercises and a treadmill, I had the brilliant idea to hop straight back into my favorite group fitness class: lower body conditioning. This class is always a challenging one, but there were nearly 100 people there this time and it was fairly obvious that we were all struggling after the break. After 45 minutes of so many squats and lunges that I quickly lost count, my legs felt like two overcooked noodles as I picked up my backpack and wobbled down the stairs.

Within twenty minutes, I had cooled down and my legs were feeling almost back to normal. By the next morning, my leg muscles were felt tight and slightly sore, but I made it through the day without noticing the soreness too much. By the second morning, I could barely walk as I waddled and cringed my way across the house getting ready for class. Let me just say that you never really notice the subtle inclines and all of the many staircases on campus very much until every step reminds you of every single squat and lunge you did two days earlier.

So why were my legs so extremely sore?

This kind of achy, sore feeling after a workout has an official name: delayed onset muscle soreness, or DOMS. While many mechanisms work together to cause this soreness, they are not all well understood. The best-understood cause of muscle soreness is simply that strenuous exercise causes microscopic tears in the muscle, leading to inflammation and soreness as part of the healing process.

The eccentric phase of exercise may be particularly responsible for these tiny tears. This is the phase where the muscles are lengthening, so if you were doing bicep curls with a dumbbell, the action of lowering your had back down to the starting position would be the eccentric phase of the exercise. This phase of the exercises puts more load and strain on your muscles, leading to the micro-tears.

Often, you might hear people say that soreness comes from lactic acid build-up in the muscles. While lactic acid is a by-product of your body’s metabolism during exercise, the lactate is cleared from your system naturally in less than an hour, usually, and is not the cause of your muscle soreness later.

 How long does the soreness usually last?


Photo from

Most people experience peak soreness 24-72 hours after an exercise session when it’s something that they haven’t done in a while, if they are new to exercise, or if they greatly increase the weight load of the exercise compared to what they usually do. The good news is that after one bout of terrible soreness, like the one I experienced last week, you should feel back to normal in 3-5 days and the same workout isn’t likely to make you nearly as sore again if you continue to do it regularly. If you feel sharp pain WHILE you’re exercising or if your soreness doesn’t go away after five days of resting your muscles, you may need to consult a doctor to see if the pain is due to an injury and not just general soreness.

What else should I know about exercise-induced muscle soreness?

  • While studies have shown that medicines like Tylenol or ibuprofen may help with the pain, the results aren’t definite and they don’t help your muscles recover or heal more quickly.
  • If you’re not sore after a workout, it doesn’t mean that your workout was too easy or that it wasn’t “good enough.” The level of soreness is simply related to your level of muscle adaptation to that particular exercise, as well as your genetics.
  • While stretching, warming up and cooling down are still super important for keeping you safe during exercise, they have not been shown to reduce DOMS.
  • The micro-tears are not bad for your muscles, they are simply a natural consequence of tough exercise and they heal themselves naturally and strengthen your muscles in the process.

How can I recover more quickly from my DOMS?

Unfortunately, there is no definite way to make your soreness dissipate more quickly. No vitamin, mineral, or herbal supplements have been researched and proven effective for specifically treating DOMS, and you should ask a doctor before taking them. Massaging the muscles by hand or with a foam roll may be your best bet, because even though it is painful at the time, it increases blood flow to the muscles and may help them heal a little more quickly. There is no guarantee of what will work for you because every person’s body is different, but I usually feel a little better after a hot shower and after massaging the sorest spots.

Muscle soreness from exercise is a badge that some wear with pride and others, including myself, just try to minimize and get it to pass as quickly as possible. If you came running to work out with Campus Rec last week during “Spring Into Fitness,” and you were left as sore as I was, don’t be scared away! The worst has passed and your muscles are better prepared for your next workout, so come back to work out with Campus Rec during this chilly four-day week and be proud of the hard work your soreness represents!


Workout Wednesday blog posts are written by UNC Campus Recreation. Each Wednesday we swap blog posts with the Tar Heel Tone Up blog so that readers can view more diverse post topics that will benefit their health and wellness. Workout Wednesday blog posts can be found both here and on


Why are Your Muscles Sore After a Workout? 22 July, 2015. Greatist.

Yu, Christine. No Pain, No Gain? 5 Myths About Muscle Soreness. 17 July, 2014. Daily Burn.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s