“My [GLUTES/LATS] are sore so I know that I was using them!”
“My [QUADS/BACK] are always sore after I [SQUAT/DEADLIFT] so I know that I was doing it incorrectly…”
These are phrases commonly heard around the gym. And, as one would expect from me, I get a little annoyed every time I hear someone say something that is kind of incorrect, but I do often resist my urge to chime in with an obnoxious and unnecessary clarification.
Instead – I am saving my corrections for this newsletter!
DOMS (Delayed Onset Muscle Soreness) is caused by the eccentric (lowering phase) contractions of muscles. Meaning – you get sore from lowering into a squat, not driving yourself up out of the hole. You get sore from swinging down from the top of a toes-to-bar, not from pulling your legs up. Your traps get sore from pulling yourself under the bar on the snatch and clean & jerk, not from pulling the bar up.
While the exact mechanisms of DOMS are not fully understood, it is likely due to microtraumas to the muscle and subsequent inflammatory responses. It is DEFINITELY not from lactic acid, though (that’s a whole different rant).
There’s also an adaptation to training that occurs that limits DOMS in exercises that you are used to. This is likely a combination of both neural adaptation to the training reducing the amount of pain felt (kind of like when your thumbs finally get used to hook grip and stop hurting every time you grab the bar) as well as adaptation in the actual muscle itself as it restructures itself on a cellular level to the types of stress imposed upon it.
So, when do people get DOMS? When they do high volume eccentric contractions of exercises that they’re not used to.
What does DOMS tell you about which muscle groups you were “using?” Not a whole lot.
Not only is the paradigm of thinking about muscle groups as being “active or inactive” flawed, DOMS really doesn’t tell you anything about relative activation level compared to a theoretical optimum.
All it tells you is that you did more eccentric contractions and/or a different movement pattern than you’re used to.
So, what’s the deal with “active vs inactive” muscle groups?
There’s both a theoretically optimum contraction intensity of various muscles surrounding a joint to move through a specific range of motion. This contraction intensity splits the load amongst the various co-activators and keeps the joint centered (in terms of “roll, slide and glide”) as it moves through a range of motion such as hip flexion or shoulder extension.
However, since our bodies are dynamic systems, we never really do the same movement twice. The actual activation of muscle groups changes every single time we perform a movement, as the brain operates in gross motor patterns (ie “reach out,” “walk,” etc.) and recruits muscle groups on the fly to achieve these larger movement patterns.
It’s pretty much impossible to squat “without using your glutes.” And, the number of people training in a CrossFit gym who have “weak glutes” is vanishingly small. Just about every athletic individual has the contractile potential in their muscle fibers to to accomplish the tasks that they want to do.
Instead, we tend to have altered motor patterns as well as overly facilitated and overly inhibited muscle groups.
So, for example, an athlete may struggle to achieve true hip flexion in their squat since they they struggle to balance through the hip as they load it eccentrically – then they overarch their low back which creates an impingement opportunity in the anterior hip and also inhibits a lot of the musculature throughout the pelvis that creates proper stabilization and control over the arthrokinimatics (“roll, slide and glide”) of the hip joint.
Does that mean that they need to strengthen their glutes? Or that they need to learn to activate them? Or that soreness is indicative of a better squatting pattern?
Not really on all counts.
What they need to do is retrain their default stabilization strategy such that they more evenly spread the load of controlling joints through movement patterns across the muscle groups that attach at those joints.
Will that result in increased soreness?
Soreness is nothing more than an indication that you did more eccentric contractions in a specific movement pattern than you’re used to.
Soreness after a training session and ideal joint control during that session are (almost entirely) independent variables.