Friday is a bad day to start things and 13 is unlucky. So let’s start something awesome this Friday: tuck jump burpees. We’ll do 13. And then another 13. And then another 13. And then one last 13. That’s our Friday challenge: 4 sets of 13 tuck jump burpees. What?! YES!!

To do a tuck jump burpee, do your burpee (including the pushup) and end with a powerful jump straight up, bringing your knees toward your chest while in midair. If you can, grasp your knees quickly with your arms as your thighs touch your torso. Release and land. If the full tuck is not going to happen, hold your hands out and bring your knees up high enough to tap them against your hands. These 13 burpees are going to go a lot more deliberate than regular burpees because to do the tuck…well, when you do your first one, you’ll get why you have to pause and reset before every burpee.

Land softly like ninja.

If you are experiencing knee pain, take more time between jumps to reset: get your body aligned, and when you land, allow yourself to come down into a fuller squat to absorb the impact. If there’s still pain, stop jumping. Sub 10 standing calf raises _ 2 squats for every jump, off a stair or ledge if possible.

You should spread your 4 sets out throughout the day. And it’s not just OK to pause in the middle of your 13 and rest; it’s preferable. This is not a conditioning workout. Better to have jumped high and with extraordinary elegance 13 times than to be out of breath from 13 fast half-tuck burpee-y things. You’re going for a super explosive explosion of an upward jump at the end of every burpee, because so many things in life should be a super explosive explosion of an upward jump.