Hi. I’ve recently been spending a lot.more.time.playing - perhaps an hour or so a day. I’ve always had a weak.lower back - operations and implants - but have begun to develop a painful left shoulder. I don’t think I’m gripping the neck tightly at all…But I do tend to sit askance on the sofa and hunch over the guitar.
Any advice on correct posture and fixes to my -maybe? - bad habits?
Scott,
I started having lower back problems and started using the classical guitar position, guitar on inner thigh and and foot stool on left foot (right handed). Not for most peole but it worked for me.
Thanks. It did cross my mind. Standing also, or at least a short guitar strap while I’m sitting to pull the instrument up? I guess it’s just trial and error.
Scott,
Whenever I play on the sofa, my back feels sore & strained. I don’t have the same issues when playing in an armless chair… because of this, I rarely play anywhere other than a chair these days. Hope this helps!
Tod
Thanks Tod - Also makes sense. I need to be more intentional about where and when and generally less casual about my practice sessions. 
I have significant and permanent back issues, so out of necessity have had to really educate myself about posture and tension.
First I put the guitar on the left leg some time ago. Originally for back reasons, I’ve found over the last 2 years that it’s much more efficient as well.
Also, always use a strap.
Re, the hunching over/ sitting askew on the lounge. You don’t need me to tell you the issue with that. For any lounge playing, I either put pillows behind me and/ or sit on the edge of the lounge, always straight.
Re the painful left shoulder. Check if your right shoulder is cocked high, which seems very common. This will mean you are ‘leaning’ into your left shoulder; possibly the cause of the pain. Shoulders should be pretty much level.
If you have a back brace, there’s no problem wearing that at times to help out, although I wouldn’t suggest relying on it.
There are many good videos on posture/ tension on the internet ( and some shockers)…
Justin has a brief topic on posture here
To test if you are gripping the neck too hard, try fretting some notes until they sound clear. If this is much softer than your usual grip, then you are playing with too much tension.
The above is just my experience and opinion. Professional medical advice may also help if your pain persists/worsens.
Cheers, Shane
I have 5
broken/collapsed vertebrae and all of my my bone structure has changed due to severe osteoporosis …so very aware of dealing with back pain …
weight of guitar is a very big thing for me…[if weight of a guitar is a thing](With search function lightest guitar if weight of a guitar is a thing
This one I post of the many posts about posture while playing…chairs also feature in many when it comes to preventing or eliminating back problems…I see that while I’m typing, Shane has posted a lesson from the topic I’m posting… … take the time to read everything and…
watch your back 
Good luck and greetings
Thanks Shane. I hadn’t see Justin’s video on posture. Everything you say makes sense. I did see an osteopath recently who prompted me to think about posture more mindfully. I was beginning to think regular use of a strap would be a thing to try. Also, good tip on leaning into the shoulder - fairly sure that’s what I’m doing.
Thanks again for taking the time for such a through response!
Cheers Roger. I’ll read those posts with interest.
Play with a stack of books balanced on your head!
I would start by getting a good chair. If I am on the couch, I sit at the very edge of it.
We have several threads about playing position and posture to look through.
I also play classical position and my main reason was my left shoulder. It brings the fretboard up and closer and depending on where you place the guitar can bring the fretting arm in a bit so there is a lot less reach and less need to hold the arm up.
Take an old office chair, lower it so your feet are flat on the floor and your thighs are parallel to the floor. Sit up straight but relaxed and then, from that position find how you want to hold the guitar and how to keep it there.
Looks like you are sorted Scott cheers Hec
Cheers - good solid advice. I’ll give it a try. (And here I was hoping folk would tell me to buy a new (lighter) guitar )
Seems many of “we” (insert your sub-group here) have musculo-skeletal issues.
If this pain thing is not an isolated instance, I’d suggest maybe invest in time with a good physical therapist.
At 65, my body is beginning to give up on compensating for a lifetime’s “bad” posture. Learning how to properly use different muscle groups from a physical therapist has been a life changer for me. I may not be able to prance like Mick Jagger when I’m 80+, but I hope to be comfortably playing guitar at his age.
Scott, forgot to mention standing and using a short strap as well. That helped as well. Doing daily stretching exercises is also a must.
For me the problem seemed to stem from looking down at fret board. Holding the weight of something the weight of a bowling ball between your shoulders took its toll on my lower back.
Forced me to hold my head up straight and really learn the fretboard. Turned out to a blessing in disguise .
Good luck!
Well aren’t we a beat up bunch of guitarists. Maybe it’s time for Justin to open a back clinic.
I have dealt with lower back pain from spondylolisthesis (misaligned verterbrae) for 25 years. All of the suggestions above are useful @scottasaigon. It will take experimenting and time to find the most comfortable position. You mentioned having the strap hold up the guitar neck. You really don’t want that. Use a strap, but when you play the guitar should be held in position by your upper arm and thigh, with minimal support by the strap.
I think you’re right but I suspect in many cases playing guitar is just highlighting the issues caused by the rest of modern life, with many of us working at computers, scrolling on phones, driving a car and slouching on sofas which often adds up to the majority of waking hours.
It’s an odd thing that the comfiest seat in my house (the sofa) is the worst for playing guitar and the least comfy, a simple wooden dining table chair is the best but it’s true.
When I started doing yoga in my late 40s I quickly realised how bad my posture was becoming (in general, nothing to do with guitar playing) - even just trying to sit upright, unsupported on the floor was a problem. It was something of a wake up for me, particularly as someone who considers themselves to be active, that if I was like that in my late 40s, what would I be like in my late 50s or 60s 
it certainly wasn’t going to get better by itself. The good news is it can be corrected but it takes time and persistence
Just to reiterate mostly the same things. If you just think logically, sitting slouched on sofa curled over guitar an hour per day is going to cause issues. Probably more important than how you sit is just that you sit differently. I generally mix up sitting / standing and where I sit etc. Sometimes on the sofa, sometimes on a hard back chair, sometimes standing with a strap, sometimes standing with one leg up on a bench (to prop up guitar).
I am no scientists, but I imagine mixing things up isn’t a bad thing for posture / muscles / body, and also I think it improves the playing, just getting your body used to playing from different positions. Most of the time, if you play for other people you don’t get to recline on the sofa.
Similar to what @mattswain mentioned, I found that near the end of BLIM Class1, I was having picking elbow troubles. I researched that it was known as cubital tunnel syndrome - basically inflammation of the nerve channel that goes through the soft area of the elbow.
I began by blaming it on more frequent guitar playing, but realized that it was probably more likely to be poor posture in my work day. I was resting that elbow on a desk edge and starting to lean on it.
Examine your daily activities and see if there is something there that also causes discomfort that needs to be corrected.
Be sure to hold your head up throughout any activity you can. For shoulders, they should be back and down - push your chest up and out to get the idea. This is possible even when reaching forward for typing on a computer. Yes, I am doing that now.
Yep, I think I’ve just been lazy. Time to take things more seriously.
I’m not.good.in any position for a long time, so need movement to feel comfortable. So yes, a decent strap, standing sometimes, getting hold of a music stand and no more slouching on the sofa!