It’s not uncommon as we get older to experience physical pain when practicing guitar. The best way to deal with this is to develop good habits early. The main areas that become a problem are the hands/fingers, shoulders and back.
I’ve dealt with back pain for quite a while and and have found quite a few ways to deal with this. If this applies to you check out my fairly extensive lesson that you can access here:
If you haven’t experienced this issue yet I still encourage you to make sure you’re using good posture when you sit down the practice. It’s natural to want a slouch over the guitar to see what you doing, but this is likely to cause you trouble later.
One thing to look for if you’re experiencing pain in your left hand or fingers is that your guitar is not set up for easy playing. Sometimes it takes so much effort to press down the strings that it strains the muscles of your hands.
If you think this might be the case I’d recommend having your guitar adjusted by a professional. I’ve created a more thorough lesson on what to look for and what your option might be.
The other issue is you may be overcompensating for incorrect finger placement and using too much tension.
If you’d like to learn more about this issue and how you can develop good habits to help protect you from hurting yourself in the future check out this complete lesson: