Straight Blast: boxing is an excellent exercise, sport, and hobby, if you start you should have a lot of fun, get a good workout, devlop speed, timing, power, a sense of distance, and a good trainer/teacher wont let you spar hard enough to get hurt intill your ready. but in addition to boxing try to incorparate some other self-defense work, adding kicks, hand weapons such as palm heels, chops, elbows, holds, locks, chokes, defense's ageinst back and weapons attacks, chokes, and grabs, ALSO make sure that you emphzies developing a mindset that thinks about self-defense without being parinod, and is 47 to old to start? well, the odds are you may not have time to win a world championship, but it's never to late. good luck, train hard, train smart.