Burpees or Squat Thrusts are another advanced exercise that will challenge your legs and your heart. By going all the way down to the floor and back up again, adding a jump on the end, you'll feel your heart rate climb very quickly.
Burpees (good for toned legs and bum). From standing, squat down and place your hands either side of your feet, and shoot your feet straight back. Jump your feet back in and then jump back up to standing.