Do this quick high-intensity workout with the cardio exercise of your choice: running, swimming, biking, elliptical, you name it.
Justine Zwiebel / BuzzFeed
Learn how to do the challenge here and jump into it anytime.
1. You'll start with 60 seconds of "work" (running, cycling, rowing, elliptical, etc.) followed by 60 sense of rest.
2. During the work intervals, your level of effort should be about an eight on a scale of one to 10. In other words, you should be going at about 80% of what would be your all-out maximum effort. If you can carry on a conversation, you're not pushing yourself hard enough. If you can't even get out one or two words, you're going too hard.
3. Your rest intervals can be either complete rest or very light effort.
4. The first time you do this workout, you will work for 60 seconds and then rest for 60 seconds — that's one round — and then repeat the couplet seven more times for a total of eight rounds.
5. Do this workout once per week, adding two rounds each time you do it.