Karate has many benefits but not the least of which, it is a great way to get into shape. Why you might ask, well if you stop and think about it and remember back to the last schoolyard fight you got into as a kid – fighting takes a lot of energy! I remember in the eighties I thought of billing, “Karate Aerobics” as a way to get into shape but I did not ever get this off the ground. Many others have thought of the aerobic benefits of karate since and have karate workouts for their clientele. One of the most famous is Billy Blanks, Tae Bo workouts. Here is a short video.
I have just started to work out on the heavy bag in my workouts. The great thing about karate, boxing or MMA and bag work is you can get a good workout without getting hurt. I do workout with karate normally but have laid off for the past couple of years while I was pursuing my masters (MBA) degree. You may be wondering whether to take a Tae Bo class or just go to your local gym or dojo to get the work out. That depends on your goals.
If you go to the gym or dojo to get your fighting lessons, you will get a great workout but also learn how to defend yourself. If you take any karate aerobics class you will get into great shape also but (hopefully) not delude yourself that there are any ancillary fighting knowledge departed to the students. By the way, Billy Blanks is a great fighter but his Tae Bo is worthless as any karate aerobics would be for fighting knowledge.
I attended a few classes at a 24 Hour Fitness gym and was surprised that the instructors were teaching punching wrong. The were teaching everyone to punch with their back straight and chins up (to look good) instead of maintaining a defensive posture. I brought it up and they really had deluded themselves that a person could have a takeaway some self-defense moves from attanding a karate aerobics class. 
Anyway if you decided to incorporate some type of martial arts training into your workout, please examine what your goals are and then seek the trainers you want.
With so several weight lifting programs obtainable it was really tough to choose the correct 1 for me. Once I found 1 that got me results I stuck with it and I simply modify it occasionally.