I recently gave up on Brazilian jujitsu. I love the sport, but my body is mangled - cauliflower ear, scar tissue on my eye, beginning of arthritis on my finger/hand. This is after only 3 months of consistent training. I am interested in Japanese jujitsu, but there just isn't any information about it out there. For those of you who have experience- 1. How is the cardio in Japanese jujitsu? 2. Is there a lot of grip training that would lead to arthritis? Any information would be greatly appreciated, thank you.