The key to interval training is push to max effort during the high intensity period (work) and then rest from cardio (but keep moving) during the low intensity period (recovery).
Interval Training in 5 Easy Steps
1) Decide what kind of workout you want to do: What are you in the mood for or what can you do? I'm all about what you can, when you can so I mix things up. There are lots of interval training options like HIIT, Tabata, sprints (run, elliptical, swim), even jumping jacks alone can be your workout. Any type of aerobic workout will work. Pick what works best for you, but at the same time will challenge your body.
2) Plan your intervals: Again, so many options! If you are just beginning, you will want to start with a work to recovery ratio of 1 to 4 which means your recovery will be 4 times longer than your work. For example: 5 seconds work to 20 seconds recovery or 30 seconds work to 2 minutes recovery. As you become fitter, you can adjust the work to recovery ratio so that you spend more time at max effort and less time in recovery ---> 1:3, (intermediate) 1:2, 1:1. 2:1, (advanced) 3:1, 4:1.
3) Warm-up: I highly recommend doing at least 10 minutes of easy warm-up (like walking) before doing high intensity workouts.
4) Use a timer: This will make doing your workout so much easier. Instead of staring at a clock or your watch, download an interval app (this is my favorite) on your phone or look for something like a Gymboss timer.
5) Cool down: A low intensity cool down is just as important as the workout. The longer the cool down the better so the body can metabolize the fat it was using during the workout instead of letting it return to where it came from!
I really began to understand the impact of interval training when I first started carb cycling. The program I follow pairs interval training with low carb days, which forces the body to reach for stored fat as energy (learn more here). I wasn't running at the time, so I did all my interval training workouts on the elliptical or doing HIIT workouts. It's really easy to make interval training work for you.
Do you do interval training?