As humans, we want to know our workouts are making a difference and worth our time. With fitness watches, we now immediately access information that could point to our workout's efficacy. These devices can relatively precisely indicate how many calories we've burned, how we've challenged our cardiovascular system (heart rate), and even if we were in a fat-burning zone and for how long.
However, one way a fitness watch falls short is in giving us measures for how effectively we've worked our muscles, which is the most important part of an exercise routine. And because we are used to seeing data about our workouts, we look to other indicators that will prove to us whether or not we did something effective.
For many, that indicator is soreness. It feels satisfying to feel sore the day after a workout, and it's tempting to believe that we did something that got us a step closer to our desired results. However, research tells us that soreness is not a good indicator of muscle growth or your workout's efficacy.
Delayed onset muscle soreness (DOMS) typically occurs between 24-72 hours after exercise. It's hypothesized that microdamage in the muscle leads to inflammation, making the nerve endings in the tissue more sensitive than normal.
Isometric or concentric contractions almost never cause DOMS, and it almost always caused by eccentric contractions. So if your workout favored the "lowering" part of an exercise, you're more likely to be sore. Here are some examples of eccentric contractions:
The lowering phase of a bicep curl
Matrix move (or a reverse nordic curl. I call them a matrix move because it's shorter and more fun)
The lowering phase of a squat
It is hypothesized that eccentric contractions are more likely to cause DOMS because eccentric contractions cause more microdamage than other types of contractions. The muscle is lengthening and contracting at the same time, which can be more "bang-for-your-buck."
You're also more likely to experience DOMS after performing an activity that your body isn't used to. Which is good news for those exercise enthusiasts who are sore after they try something new and think, "I thought I was strong, but I guess not." You probably are strong; your body was simply challenged differently.
DOMS is not a build-up of lactic acid, as the industry once believed. The lactic acid metabolizes within about an hour after the activity has stopped.
Soreness can measure damage to the muscle, but studies show soreness does not necessarily indicate the level of microdamage to the tissue. In some cases, more severe microdamage after a hard workout showed no muscle soreness, and in other cases, almost no microdamage resulted in soreness. So level of soreness is not a good indicator of your workout's effect on muscle growth.
Exercising a sore muscle will make it less sore in the moment, but the discomfort will return once the activity has stopped. So it's not really helping decrease your soreness or allowing you to heal faster.
Personally, I don't believe you should exercise a sore muscle.
Whether or not the soreness indicates a level of damage, there is inflammation in the tissue for one reason or another. The inflammation could be for other reasons besides muscle microdamage, like from friction of bones over tissues. Because we don't know the reason for the inflammation, we should assume it's there for a purpose and allow that tissue a few days to heal. Working a damaged tissue can result in more damage, and backtrack your results.
If soreness isn't a good indication of our workout's efficacy, what is?
My opinion is to measure your level of fatigue, range of motion, and joint comfort immediately after your workouts.
Your muscles should feel tired, but you should feel "lighter" and more mobile. Your joints shouldn't ache, and you should be able to complete your daily tasks without discomfort. This indicates you worked hard enough to stimulate change, but not so hard that you incurred irreparable damage.
If you're currently feeling your joints aching after exercise or the next day, it's time to join Levo and stop settling for unhappy joints following your workouts. You can click the "Join" button at the top of this page to learn all about the membership! See you there.