In addition, research has suggested that specifically eccentric contractions (lowering a weight in which is causes the muscle to lengthen) may cause an increase in the likelihood of DOMS than other movements, which may explain why exercises like squats and RDL's leave us fearing stairs for days afterwards.
Anytime you start a new program, activity or introduce new movements into your routine you can expect some soreness to follow but is being sore after every sweat session an indicator of a good workout? Yes and no. Let's just say, it's complicated.
Bret Contreras and Brad Schoenfeld wrote a great article for the Strength and Conditioning Journal examining this topic. While there has been a fair amount of research connecting DOMS to hypertrophy (enlargement of muscle cell size) there has also been equally as much if not more research suggesting that muscle soreness caused by DOMS should not be your only indicator of a productive workout.
Before you start your next leg workout with the goal of making sitting on a toilet painful consider these important points from the Contreras and Schoenfeld article…
It could be your genes: DOMS can vary greatly from individual to individual. Some gym goers experience soreness more often while others experience it hardly ever. In other words, just because your lifting buddy is bragging that he's not sore at all but you can barely walk, doesn't necessarily mean he's stronger or better conditioned.
Some muscles may be more/less prone to DOMS: Anecdotally, Contreras and Schoenfeld note that some muscle groups may be more or less prone to soreness and despite the lack of DOMS, strength gains can still be made.
Regular exposure to specific activity may decrease DOMS: Frequently engaging in an activity may help to reduce muscle soreness over time so what leaves you stiff and sore initially may eventually taper off even though your strength may still be improving.
DOMS may potentially cause reduced range of motion and strength: In addition to general muscle soreness, reduced range of motion, local swelling, tenderness to touch and even decreased muscle strength can also accompany DOMS. If these symptoms haven't fully resided, or at least improved, by the time your next workout rolls around you could increase your risk of injury. In fact one study showed that exercise induced muscle soreness (which happens shortly following exercise as opposed to days later) can have neuromuscular effects lasting up to ten days following exercise!
DOM may potentially reduce motivation and excitement: Muscle soreness may not just affect us physically. Although a bit inconclusive, research has suggested that DOMS may decrease motivation for future workouts. If you find yourself dreading or even worse, skipping your next workout due to DOMS you may want to dial it down a notch.
Because many factors such as genetics, muscles trained, frequency of training, etc all play a role in the presence (or lack there of) of delayed onset muscle soreness it should not be the only measure of a productive workout.
Unfortunately, the verdict is still out as to whether treatments such as exercise, walking, massage (including foam rolling), stretching, supplements, or hot/cold therapy truly help but in the mean time including a proper warm-up and easing into new activities could aid in prevention of delayed onset muscle soreness.