Just a few thoughts below as I often get asked if someone is too old to learn how to play a guitar, etc. In short - your age has nothing to do with it. Unless you are so old that you have no strength left in your arms, if you are thinking about learning how to play, or getting back into playing, I must say - Go For It.
The only real disadvantage that you might have when trying to learn how to play is that adults are usually much busier than their younger counterparts due to families, work, overtime, etc. They often have much less time available to devote to practice. It's simple and in most cases true.
However, I must also mention that it is very easy to chisel out 45 minutes a day by saying bye, bye to facebook for the night or skipping the evening news. There many time vultures prying on your time.
The advantage is that by now you have learned to how to 'learn' by getting through school and various life experiences, which can actually make applying new material easier.
Unfortunately, you can't cram playing an instrument like we did before tests in school, so constant repetition through practice is what you need to do in order to get results.
I started to play the guitar late (age 15/16) in comparison to some of my guitar playing friends who started at 9. My friends were much better than me, played songs and some were already in bands while I was just trying to perfect a power chord. However, later in High School as their focus drifted to parting and going out, I made up the difference and quickly surpassed them. I also remember reading an interview with Jeff Hanneman of Slayer where he stated that he did not start to play the guitar until he was 18 and that motivated me.
I also tell younger players to 'put their time in' when practicing. Due to travel, and running a business side of things, many professional musicians do not get to practice as much as they did when they were much younger. Think of practicing like putting money into a piggy bank. There will be a time when you will need to pull out some of that practice at a later date while continuing with your instrument.
Many people ask me how much to play and it always goes back to the goal. If someone wants to play good enough to play metal songs and simple solos or even jam one time a week with buddies - then 45min to and hour a day for 3-4 months should get them very close to the goal. I have taught 100s of guitar students in person and I have never met one person whose fingers were too short, too stubby or just not meant to play guitar. And, that's the truth.
So, that's it. Hope it helps.
Metal Mike
PS. Here are some words below that I found on the internet. Not mine, but they do explain a lot of what playing music can add to your life.
Music Is Science
Music In Mathematical
Music Is A Foreign Language
Music Is History
Music Is Physical Education
Music Develops Insight & Demands Research
Music Is All These Things, But Most Of All Music Is Art
This Is Why We Teach Music
Not Because We Expect You To Major In Music
Not Because We Expect You To Play Or Sing All Your Life
But So You Will Be Human
So You Will Recognize Beauty
So You Will Be Closer To The Infinite Beyond This World
So You Will Have Something To Cling To
So You Will Have More Love, More Compassion
More Gentleness, More Good
In Short - More Life