DOMS- Another great topic that has some ongoing debate and still many unknowns (but what topic in health and fitness isn’t up for debate after all!)

I was recently interviewed about DOMS (delayed onset muscle soreness) by a fitness app and it got me wondering (and asking clients) if they had questions about muscle soreness, how it was caused or what to do about it when working out or trying a new activity. I have been asked about DOMS before but it made me realize that many people seem to have a lot of misconceptions around it.  No- Lactic acid build-up is not the cause and has now been throughly debunked.

Most of you have or will experience this if working out or trying something new or intense that you are inexperienced with, so I wrote this to summarize some of what we know (but also don’t) and dispel some myths out there. Whether you are new to working out at a gym or have been going at it with an active lifestyle for decades with plenty of experience with sore days, I hope this helps you with some practical advice from what we actually know. 

Delayed onset muscle soreness (DOMS) defined

There is no agreement on an exact definition, but you will see DOMS defined as being caused by some type of trauma to muscle tissue or nerve. It is usually hypothesized to be type I muscle strain (mild damage to muscle fiber) and the various pain and inflammation eliciting processes that occur due to it and in parallel but there are other potential causes. It is typically brought about by exposure by exercise/movement your body is not used to. This results in the characteristic soreness, tenderness, stiffness, inflammation, etc. beginning some hours after (8, 12, 17... so on) and peaking within the first few days (48-72hrs). Many will cite eccentric contractions (see above image of relaxed versus repetitively overly stretched muscle fibers below) as being the main factor. However, the time frames, the mechanisms actually causing DOMS, and what to do about it are not all fully understood and also debated (again, big surprise!)

While some may experience some delayed stiffness and tenderness 10 hours after a big day of squatting or longer than usual trail run, someone else may have that same feeling occur later or sooner, peak at a different time, lasting for a shorter or longer duration, or not at all. Why the difference? We aren’t entirely sure. But we do know that some degree of damage has likely occurred due to some degree of damage and/or some of the metabolic processes that occur surrounding that damage.

How do I know I’m not injured badly?

This was one of the first questions asked when I was interviewed but also by some clients I have had typically after a tough lower body intensive session.

Did you hear a loud pop? Did you experience pain (likely severe) right away? Or is the pain duller and creeping on gradually? While both can be sensations experienced with both severe and less severe traumas like DOMS, it is likely that a more serious injury will not present quite like DOMS. There are also sympathetic nervous system driven processes that will prevent/block you from feeling DOMS right away.

If you leave a workout feeling fatigued but otherwise fine and then start to become sore hours later that is most likely not due to an injury that should keep you away from the gym. However, DOMS can also last for days beyond the initial few that most people commonly experience and can even be part of things that are life threatening like rhabdomyolysis. Though with rhabdomyolysis you will likely also experience very dark urine, vomiting, irregular heart beat and several other unpleasant symptoms with typically much worse muscle pain. Similarly other more severe injuries will be accompanied with more severe symptoms. 

DOMS really is just varying degrees of unpleasant with stiffness, soreness, mild swelling/inflammation, and sometimes some altered movement or weakness that inhibits full expression of strength .

What causes it?

The Science! While exact mechanisms are debated, DOMS is most likely caused by some sort of trauma or damage to muscle fiber (again, most frequently hypothesized as type I muscle strains) and/or nerves (see the orange and green lines in the image below) accompanied by inflammatory processes; and some of the resulting byproducts of a variety of cellular processes that go along with the type of damage or exercise. Some hypothesize that it may be damage to fiber AND nerve as the authors of the Sonkody study linked above do, along with various other inflammatory and repair processes post exercise for repair. After all, these processes that drive DOMS are also necessary to get rid of the waste byproducts of the damage to then help you adapt and grow. Think of things like the inflammation cascade that happens from injury along with the formation of byproducts from exercise that can all contribute to discomfort, swelling and stiffness. Some of the chemical byproducts of these processes from inflammation along with those that trigger nerve growth may get mingled with pain receptors (nociceptors) outside the muscle cells and tell your brain that what you did was ouch.

The reason we usually have DOMS is from trying something our body is not accustomed or adapted too which is why you often experience it the most when trying a new sport or type of exercise. Basically, new and unaccustomed can be traumatic since the body hasn’t had an opportunity to adapt like it eventually will. It is also thought that eccentric (the lowering phase or braking portion of a movement) can make for worse DOMS hypothetically due to less motor units recruited during that eccentric phase which makes for less muscle tissue having to bear the brunt of the force.  

There are likely other mechanisms like chemical byproducts, other types of damage, or pathways yet to be discovered or fully understood in how they contribute to DOMS as well, so this will likely be something returned to for years to come. 

Is it good or bad?

Are you thinking you must have had an awesome session because you’re super sore? Maybe you’re worried you overdid it or hurt yourself because you’re too sore to sit down to go the bathroom? 

While both can be true it doesn’t mean that is the case. Interestingly it has been shown through imaging techniques that you can actually be really sore without any damage to write home about and vice versa. So, the degree of soreness does not equate to the degree of muscle damage done.  

While this may be true (and maybe also somewhat disheartening), rest assured that DOMS can still be a good indicator of damage in our experience when you do see long term adaptions accompany it like muscle strength and size increases. That’s what we’re going for after all! 

However, we can also use other factors to determine whether this is “good” or “bad” as not all DOMS are the same. If for instance your pain and stiffness is so painful that is changes how you move or you feel weak yet are trying to perform at peak condition with these muscles, that may be an instance of “bad” news. However, the same can be good if given ample opportunity to recover and it doesn’t interfere with your training (or life) too much. 

The answer here is that it depends and it’s also relative. Yep- another it depends answer but one you can at least use good judgment with. Basically, DOMS are neither good nor bad, but rather a potential indicator. Depending on how you feel and move will more importantly determine how you approach your next gym session or trail run so you don’t reinforce less optimal mechanics due to severe soreness making you move wonky or delay healing of tissue that may in fact be pretty blasted and not ready yet. 

Is it okay to work out?

THE question…Probably yes! But again, it depends as we highlighted in the example above. If you are so sore that you’re walking funny and a light jog looks like a hobbling limp, then it may not be time to go on your next trail run or squat yet. However, you may be able to hop on to a bike and go for a gentle ride to help things move along. Some concentric contractions may actually help with blocking the pain and also give the benefits of exercise. Finding something that you can do with a primarily concentric contraction versus eccentric may be an excellent option if you don’t cause too much damage too soon.

While it may be the case that doing more vigorous tearing of the same tissues may impede or worsen repair outcomes for growth it may be beneficial to get some nutrient rich blood to the area and lymph flowing to accelerate your healing. It has been shown with misee results that massage and foam rolling may help with DOMS for some of these reasons. After all, we are trying to adapt and the better we recover the sooner we can get back to it. There isn’t unanimous consensus in support, but we do find it works well with clients when we pair a gentler movement that they CAN and feel comfortable doing to keep them moving. Usually it is predominantly concentric. We are also manual therapists and use many different modalities that we have seen help with recovery. Admittedly we didn’t tend to see folks for DOMS but we have seen it help quite a bit. More importantly, we also make sure to progress things gradually with our training clients so that the body has time to acclimate to something before turning up the volume and/or intensity. This makes for a better likelihood of less DOMS down the road. 

Nevertheless, sometimes it may not be a great idea to work out if you’re so sore that it’s really affecting the way you move. Again, this can alter motor patterns or just your performance even if there may not be any risk for more damage at that time. 

What else can help?

It does appear that caffeine, taurine and omega-3 fatty acids may all help with DOMS, though in different ways.

Caffeine has been shown to reduce soreness when consumed at 5mg/kg bodyweight and would be taken before workout. However, that is A LOT of caffeine and bordering the 4-cup mark for most people. It’s hard to say what less would do as the study that used caffeine had subjects ingest a pill form at that dosage. 

Taurine appears to help with both DOMS and oxidative stress post exercise and may be beneficial though it has not been shown to help with inflammation.

Finally, omega-3 can help with DOMS and is likely due to its anti-inflammatory properties battling various inflammatory factions like IL-6 and TNF-alpha. 

Again, without full knowledge of what causes DOMS, we tend to reccomend the above recovery and exercise practices when asked, but were not endorsing it here for you as it may depend on your unique circumstance. Age, training age, health status, levels of constant low grade inflammation and many other factors can influence what may help you versus someone else.

There’s a lot we still don’t know!

As is often the case in the world of health and fitness, there is still a lot we don’t know both in regards to how DOMS occurs and what may best help with combating DOMS so people can recover and get back to their favorite trails or gyms. 

We personally like to use the above strategies combined with a training program that is periodized in a way to allow the body to adapt more gradually over longer stretches of time without too much extreme fluctuation in novel movement, volume, or intensity unless planned out. We find this works best for the majority of our clients who mostly train for health and longevity along with goals of getting leaner, stronger, and generally more fit. We also use massage practices not always to help with general soreness from workouts like DOMS but things more chronic or acute when they pop up. Granted it has been difficult to isolate exactly what type of massage is best let alone the precise mechanisms, but we see it help tremendously in our studio for a variety of issues. Nutritionally we also have seen some success with curcumin (the anti-inflammatory compound of turmeric) and other anti-inflammatory compounds when used sparingly and in the right instances as there is a balance with the essential nature of inflammation as part of healing and also when it gets out of control. Interestingly this may also be why it seems that older populations may have fewer negative effects from NSAID use on muscle growth than younger populations due in part to how inflammation is controlled more or less as we may age.

In the end, there is likely no end to what we will find with DOMS in the upcoming years and it may be a long time before we understand why certain things that appear to work fail to in certain circumstances. This is why we also like to give the advice that you should do what works best for you and so is the case with DOMS.