excercise equipment

Right, 15 mins is for the beginner. Its not time, the key is the intensity. You can do rope jumping 10 mins (non-stop) followed by jogging for 8-10 mins (non-stop) and ending at half-crunches or leg raising (5 sets with 10 reps, again non-stop). Take a break of just 1 minute while switching from one exersice to second. Follow it for atleast 15 days on daily basis without any off day. Faster result is guranteed.