Spend most of your time playing the music you want to play. That way you'll learn the techniques that are necessary for you to do what you want to do. Specific technique practice for 10-20 minutes is good to refine movements your body is already capable of making. Playing the instrument should not be physically challenging for the most part (some stretches or chord "grips" may be exceptions).
I've had some serious muscle issues that prevented me playing for most of a year, and have to use my practice time judiciously. My chops have actually improved by practicing technique less and making music more.
One thing I found interesting/useful to think about. Grab the index finger of your left hand with your right hand. Now rotate your left arm. Your index finger is essentially the point of rotation (if you grab any other finger with your right hand, it's much harder to rotate your left arm). I found this useful for efficiently moving my left hand for hammer ons and pull offs.
Best of luck to you!
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