I've been playing guitar for 31 years, and one thing I could never do is pick up a guitar and just start playing ( I've tried a few times, under pressure from other people to suddenly join in a jam session, and I just freeze up, lol ). I've always believed that one should warm up before playing, to prepare mentally and physically, just like how an athlete stretches before a sporting event. What I do before playing is stretch my fingers a little, and then play chromatic runs slowly using all four fingers ( so 1st, 2nd, 3rd and 4th frets on the first string, then the 2nd string and so on up to the 6th string ). Then doing the same thing on the 2nd to 5th frets, then 3rd to 6th frets and so on all the way up to the 17th fret. I also play the major and blues scales in several different keys. Sometimes I'll do some hammer on's and pull off's using all four fingers in various positions on the guitar, just to get the blood flowing to the fingers and to build up strength in the hand and forearm. It's never a bad idea to play a few pages of music ( real music notes, not tabs! ) before getting into some serious playing sessions. I used to read a page of music ( usually in the key of C ), then play it in as many different keys as possible ( G, D, A, E, then F, Eb, Ab and Db ). I find that playing actually music notes before playing helps you to become more focused. Or sometimes I do a lot of the warm up exercises on an acoustic guitar first, and THEN play and electric guitar. It's a lot harder I find to do it the other way around. I know it can be hard sometimes to find time to warm up properly, especially before a jam session or gig ( I've had people thrust an acoustic guitar into my hands around a campfire, and even then I'd warm up for ten minutes, much to their dismay, lol ), and there are some people who can just pick up a guitar and start playing. Nevertheless, I believe that warming up is an important part of a proper approach to great guitar playing....
BobbyCrispy :-)
I'm now 68, been playing for about 40 years. Never bothered with any sort of warm-up when I was younger, but I find that it really helps now.
I don't do anything extensive or special, but I will run chord shapes up and down the neck and knock out a few scales till I feel limber.
I'm fortunate in that despite my age, I don't seem to have any signs of arthritis or lack of facility.