Delayed onset muscle soreness, commonly referred to as DOMS, is caused by micro-tears in the muscles that occur when you put stress on them. This causes soreness about 24 to 48 hours after the workout. The soreness comes from your body producing inflammation. Once the micro-tears are repaired the muscles are stronger but technically you’ve “injured” the muscle to gain that strength. So that soreness is a natural part of the process as your body recovers and gains strength. So, what determines the amount of DOMS you experience from a workout and why the soreness may be different? A few things.  

How often you work out 

This is easily a given but when you don’t work out very often it’s easier to get sore after a workout, even when your trainer friend may have called it “light”. Your muscles eventually get used to the movements when you perform an activity more often reducing the amount of DOMS over time. The same can be said for working out too much. If your workout partner has already been at the gym doing some pretty intense exercise for an hour before your workout, then the activities you complete could possibly push their body over the threshold and cause them to experience DOMS. Everyone’s body is different so your training sweet spot might be different than others. Don’t try to match up with someone else, just because. There are a lot of factors to consider when it comes to developing the right workout for each person.  

The type of exercise you do 

Whether you’re running or lifting weights, your muscles are getting those micro-tears. However, your soreness is determined by the type of exercise you’re doing. Eccentric movements (when the muscle lengthens) cause more muscle damage than concentric movement (when the muscle shortens). For example, the downward motion of a squat, the lowering of a shoulder press, lowering the body during a crunch; all of these are eccentric movements. They’re part of any kind of workout, and actually quite beneficial to strengthening, but the intensity and concentration on these particular movements can increase the soreness you feel later. 

Hormone levels 

Did you know that estrogen helps decrease inflammation? That means women with higher levels of estrogen tend to have less muscle soreness than those with lower levels of estrogen. This will also vary with monthly cycles, hormone replacement, and life stages. This is why women in general will often experience less muscle soreness than men.  

This is far from an exhaustive list, but just with these few examples you can see that your soreness really does depend on several factors. Start being a little easier on yourself when comparing your body to others’. Just because you have a different level of muscle soreness doesn’t mean you’re more out-of-shape, did an exercise wrong, or didn’t push yourself enough. Everyone’s body is different which means different levels of DOMS for each of us. Keep moving.