I see there are plenty of good challenges on here but I want to know what you guys think would be the best one for someone who is relatively new to jujitsu and needs to improve both flexibility and cardio. I would like to get a challenge and work towards first completing it and then lowering my time. Not too long ago I was gasing out during drills and im still having a hard time although its getting a bit easier. I just want something I can work on when im not at jujitsu class. If it helps im 5'11 245 whitest of white belts, have a little experience with Mauy Thai.