I’m not as sore as I used to be, are my workouts less effective?

TLDR: You’re most likely to be sore when you first start off, but it in of itself is not a good thing. You tend to get less sore over time with consistent exercise, but most likely as you get less sore your workouts are actually becoming more effective. But, if after months of consistent training you’re never sore, it might be a good sign that you can do more. 

For a long time we thought that we grew new muscle when it was ‘broken down and built back up.’ Within this framework, we assumed that a sore muscle was a muscle that was ‘broken down,’ a necessary component of growth. But new research has pretty thoroughly debunked this idea. We understand much better now that, while we do create damage in our muscles when we lift weights, it is not understood to be a key driver of muscle growth. Lifting weights generates tension in those muscles and it is this tension that sends key signals to our dna to build more muscle. Too much soreness can actually be counterproductive, as our body has to divert resources to repairing that damage instead of just building new tissue. 

Our understanding of soreness has changed as well. We now understand much better that what we perceive as soreness is a product of trauma to our fascia, a layer of fibrous connective tissue that weaves throughout our muscles and soft tissue like a web. That debilitating feeling in your glutes the next day after doing bulgarians is a product of your nervous system sensing the damage to your fascia, not muscle. And fascia alone has nothing to do with muscle growth outside of the supportive structure it provides to our body.

So why do we get sore? We tend to be the most sore when we have taken a long layoff from lifting weights, or when we do movements that are new. We also tend to get very sore from doing exercises where the hardest part of the exercise involves the most stretched position of the muscle. So if you have not worked out before and your first leg day back involves squats, romanian deadlifts and bulgarian split squats, you will probably be very sore. But do that for six weeks in a row and you will get consecutively less and less sore each week. Did your workout get less effective? No, it actually got more. 

Ok so should we ignore soreness completely? Probably not. In some specific contexts, tracking your soreness might be worth doing. For one, the exercises that tend to make us the most sore are also those that are the most effective for building muscle. So we can generally expect to be decently sore a lot of the time if we are training efficiently. As we overcome the initial stages of lifting weights, soreness can be a good indicator of how much our bodies can tolerate. If we are never sore after months of consistent training, it's probably a good indicator that we could do a bit more. Alternatively, if you are seeing good progress towards our goals and you are never sore, don’t feel like you have to change a thing. Soreness could be one variable to track, but is never going to be more important than your performance in the gym over time.