Learning guitar and learning martial art are very similar in nature. Playing guitar is like a mini martial art of the fingers. You have to work on moving from position to position; using just as much movement and force as is necessary. You have to figure out what actually works in a real life situation (actually playing music/actually being in a real life combat situation), and what is a waste of your time. There also tends to be a lot of internal growth that develops as you train and get better. In the book of five rings Musashi said if you want to get good at sword, practice guitar. The arts compliment each other and help you grow!