First, let me explain what "interval" training in a cardio mode is. Basically, it's a variation of the intensity within the workout period. For example, let's say you're used to jogging at level 5 on the treadmill for 30 minutes. Now you're going to "cycle in" several "intervals" of level 7. If you're jogging outside, or not using equipment that can be measured in levels, you're going to have to judge this for yourself, strictly by feel.

For example, take the general pace you jog at, then "cycle in" the prescribed number of intervals at a faster rate. It's as if you were suddenly doing a wind sprint and then slowing back down to your regular pace. This cycling in pushes up your anaerobic threshold (your "top speed" before you run out of steam), burns a lot of calories and keeps the workout interesting and challenging.

Do the recommended number of sets of each exercise before moving on to the next exercise. Rest for no more than 30 seconds between sets.

1. Warm-up and stretch.
2. 60-second rope skip (just once).
3. Basketball Jumps: Crouch down like you're about to try to jump as high as you can, as if you're going to try to touch the highest place on the wall that you can reach. Now spring up as high as you can, reaching above you like you're trying to throw a basketball in the air as high as it will go, and land back down in the crouching position, making sure to land on the balls of your feet, not flat footed. Repeat for 8-10 reps. (Note: These are HARD! If you can't complete 8-10, do as many as you can, working up to 8.) Do two sets of 8-10 reps.