Since I started Aikido, i have had to run 2 miles a day and do cardio workouts for about 30 minutes a day. It isn't mandatory, but it helps out with endurance and your ability to possibly overcome someone in any kind of a fight. Also, i have been sparring with many kids to get my tolerance up. The more you fight, the more your body starts to adapt and be able to take a hit. I have been doing mostly body sparring, mainly because i do not want to go to school with a black eye everyday. But body sparring is much more beneficial than any other kind of sparring in my opinion.