Ive started to jump rope and let me tell you. What an awesome cardio workout. Also works calfs and legs endurance wise. And lats and shoulders a wee bit. So far i love this. At first i wasnt very good but now im doing really well. I feel a lot better and im looking pretty mean and lean. I wasnt fat before but the skin i burned off in my abs has revealed my 4 pack. So far im addicted. Im going to get a good heavybag to hit. A trainer has told me thats why boxers are so fit, skipping and punching the bag. U dont want to hit it as hard as u can but lightly and get those muscles working. Id reccomend this to anyone. My knees arent the best but i do this on carpet and it is a bit harder to do but easier on the knees. The rope was only 11 $ so u cant lose. Just thought id let you guys know. Cheers.