Hi there, jumping rope is an excellent form of fitness – provided you have no knee or join issues, as it’s very high impact. Because it is such an intense exercise, you can burn a lot more calories in less time than traditional cardio like running or cycling. To build up your endurance, I suggest always practicing in intervals, where you intersperse regular jumping with sprinting intervals. If you practice this even just 10-15 minutes 3-4 times a week you will see a difference in a matter of weeks! As always, strength training is so important, and I would get heavy with the weights at least twice a week for real results. The weights should be heavy enough that you can only just manage 3 sets of 10-12 reps in each exercise. This is what will build lean muscle faster, and what will keep you burning calories long after you finish your session.