Vail Daily column: Why do I feel the post-workout ‘burn’?
Last week, I received a question from a trainee regarding muscle soreness. Jim was so sore from a previous workout that it negatively impacted his ability to perform basic rudimentary tasks for an entire week.
Jim was experiencing DOMS, or delayed onset muscle soreness, after a bout of high repetition front squats. I want to discuss this occurrence in detail and make recommendations on how to avoid it.
For years, experts thought that DOMS was a byproduct of lactic acid accumulation in the muscles. Lactic acid is produced when there’s a lack of oxygen available for working muscles to derive energy; without oxygen, the muscles must produce the required vigor by converting stored carbohydrates into energy. When this takes place, lactic acid is often accumulated in the muscles at a faster rate than which it can be metabolized, causing “the burn.” The mechanism by which this all happens is more complicated than that, but this is a good working example.
DOMS isn’t caused by excessive lactic acid accumulation. DOMS is created by ultrastructural disruptions and tears in the myofilaments of the muscle. Essentially, the muscles’ most basic connective tissues tear, leading to bleeding, swelling and pain.
When does it happen?
The real question is why does this happen only under specific exercise scenarios? We know precisely that DOMS happens when a trainee disrupts their system by engaging in new activities, particularly activities that contain a substantial loaded eccentric muscle contraction. Muscles either shorten, lengthen or stay the same length to engage human movement. For example, straighten your right arm out in front of you, palm facing the ceiling, and place your left hand on the front of your right biceps. Bend your right elbow, continuing to pinch your left hand in the crux of your elbow. Your left hand will initially feel the right biceps muscle shorten, effectively pulling your lower arm up pinching the left hand.
As your biceps lengthens, your arm will return to the original state. Often, muscles will stay the same length throughout a movement to protect specific joints. For example, the muscles of your arms and shoulders are constantly shortening and lengthening during a pushup. However, your abdominal muscles are contracting hard to brace your spine, but they aren’t changing length. This is an example of a classic isometric muscle contraction. Eccentric muscle action, or when a muscle lengthens under the duress of an external load, is strongly implicated in DOMS.
Here’s a more practical example. Imagine you are standing in front of a couch. Bend over, and pick up the end of the couch. As you lower your body into position, the muscles of the thighs lengthen. You grab the couch, and as you stand up, the thigh muscles shorten with the addition of an external load, the couch. This is a prime example of a concentric, shortening muscle action.
Conversely, let’s look at what happened to Jim. He was front squatting with a heavy weight. He was upright, weight racked across his shoulders, and he sat down deep into a squat. As he descended, his thigh muscles lengthened (eccentrically) under the stress of a heavy load.
The stark difference between these two examples is that during the former, the lifter bends down without an external weight initially, as his thigh muscles lengthened. The latter, Jim’s thigh muscles lengthened with a massive load on his shoulders.
Mind you, even though the former example lifts a couch, the weight of the couch wasn’t a variable when he bent over as his thigh muscles lengthened; they only shortened under the duress of additional load. The latter example, with a heavy weighted eccentric muscle contraction, is a sure fire way to induce DOMS.
The other factor that promotes DOMS is the execution of exercises or movements that aren’t regularly practiced. As an individual adjusts to a specific exercise or movement, DOMS is reduced over time even if the weight or repetitions are increased. If you don’t want to be sore and stiff all of the time, then stop changing your workout every day or week. Perform the same exercises over and over again, yet change the weight, reps, speed, rest periods and sets. You can still progress in the midst of performing the same old exercises day in and out. When it comes to heavy focused eccentric movements like weighted squats, lunges, bench presses and bench step-ups, perform no more than five reps initially, and increase the load, reps and sets over time.
I hope this clears up the confusion. Keep the questions coming, and let’s keep talking about this stuff.
Ryan Richards has a B.S. from Ohio University and is a certified strength and conditioning specialist through the National Strength and Conditioning Association. He is the personal trainer at the Sonnenalp Golf Club and the owner of R2HP, an athlete consulting and personal training company. Richards’ passion comes from overcoming childhood obesity and a T1-L3 spinal fusion. Contact him at http://www.r2hp.com or 970-401-0720.
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