Leave Your Upper Traps Alone
It's pretty common that people work on muscles that are seen the most. We call those the "beachbody" muscles. You know, the chest, the arms, the abs and then those upper traps. From my experience, it tends to be the men at the gym that I see crankin' away at those upper traps shruggin' away. Now don't get me wrong, I don't think that shrugs in of themselves are innately bad. There are very few exercises out there that I think are "bad". It's all about context and balance.
The biggest thing we want to avoid when training is developing muscle imbalances. Now why is that important? When you overwork one type of movement, muscle or muscle group over the opposing muscle group, you develop an imbalance that will most likely have negative side effects. For instance, I myself had a huge muscle imbalance that I'm still working on: my chest and my back.
I loved to bench, I loved pushups, I love dumbbell incline, decline, flat, whatever kind of pushing motion I could do, I'd do it. But when it came to pulling, I was weak and didn't train it as much as I should have. Because of this I developed a very rounded posture where my shoulders rolled forward and my pecs were so freakin' tight, it caused me pain. Yes, pain. Because I neglected my back for so long I developed pain in my shoulders in a pinching sensation, and my posture was horrendous.
I was stuck in the "beachbody" muscle mentality neglecting so much of what I needed to be a functional human being and avoid pain. I neglected to train my posterior chain, or the back of my body. I'm here to tell you to Leave Your Upper Traps Alone. We sit all day, with our posture rolled forward, and our shoulders hunched up by our ears. Being in this position often, your body gets used to it, and those muscles surrounding your neck and upper traps get super tight. If you follow that tightness to the gym by shrugging heavy weight, you're only adding to the problem. You NEED to train your lower traps.
1. For Good Posture
I can tell you to fix your posture 20 million times but if the muscles on your back (like the lower traps, rhomboids etc) are too weak, you'll end up right back to round-back. Your body is going to stay where it's used to, where you've lived your life at. And if that life has been lived rounded, you will stay rounded. You can change this with the right help! Work on those weaker muscles to actually help un round your posture and keep it there without much effort by you. If those muscles are strong, they can keep you there, you just have to train them to do so.
2. Overhead Stability
If you put anything up over your head whether it's a barbell, dumbbell, or kettlebell, you need strong lower traps. They help pull your scapula (the angel wing bones on your back) down to stabilize your shoulders in that position. If your lower traps are weak however, pulling those scaps down is going to be that much more difficult. Scapular depression (or again pulling your scaps down) is such a key movement for overhead stability that not a lot of people are doing. With the assistance of the lower traps (and serratus anterior) you can effectively put your shoulders in better position to mitigate injury risk, so you can train harder for longer, and on top of that you'll have better shoulder mobility because you'll actually be able to maintain control of your shoulders overhead under resistance. With the right program, you can build your shoulder mobility up to actually be able to press heavy weight safely.
3. Avoiding Pain
I don't care if you're putting up 20lbs or 200lbs, everyone hates pain. Like I said with my example, muscle imbalances lead to pain eventually. They lead to compensations, they lead to some part of your body being excessively tight and shortened, while the other part and weak and elongated AND tight. Yes, muscles can be long, weak and tight all at the same time. Crazy, I know. Some people not experience the pain right away, but somewhere down the line, it'll creep it's ugly head out. When you're in pain, everyday life becomes hard, let alone going to the gym. If we can avoid this, why not do it? If we can avoid pain, why not spend 5 minutes training a lagging muscle group? It's a pretty easy exercise to do, and I can show you how to do it.
Just to restate this, I don't think shrugs are bad, I don't think training your upper traps is bad, I am saying that we need balance. Balance is the key to all things. SUPER cliche, I know, but it's true. If we can keep ourself in balance and avoid pain, avoid being super tight and immobile, we'll be able to keep hitting the gym, keep burning fat and keep looking and feeling good. You won't care about your big traps when you're 70 and in pain, I promise you.