The following post was originally featured on Fit Bottomed Girls and written by Jenn, who is part of POPSUGAR Select Fitness.

Remember how Jared shared that “progressive” workout he did with Kristen that had all of our bums and calves burning from all the jumping? Well, in it she referenced a workout I shared with her, and I thought, hey, maybe everyone will want to see that, too! And, guys, I hope you do because a) eyeballs keep the FBG lightbulbs on, yes, but, b) this workout is — in the immortal words of Bob Harper — “no joke.”

Like Kristen’s workout, you add on as you go. But, unlike Kristen’s workout, you don’t add on after each time through the circuit. Instead, you add a new move on every five minutes. So, those first five minutes, you’re doing a lot of burpees and wall ball. And then, once you get into the second five minutes, you’re doing burpees, wall ball and kettlebell swings. Between 10 minutes to 15 you’re doing burpees, wall ball, kettlebell swings and mountain climbers. Then, for the final five minutes you’re doing all of that plus jumping rope.

Like whoa.

As you go through it, be sure to count your total number of rounds completed. It’s just 20 minutes long — but by the end you’ll be amazed at how many burpees and wall balls you did. (And surprised at how long the final rounds take — I only got one full round in my last five minutes!)

Looking for a no-equipment version of this workout. Oh, I got substitutions. No excuses — you can do it!

No-Equipment Modifications

0:00 to 5:00 minutes:
5 burpees, 10 squat jumps

5:01 to 10:00 minutes:
Add 15 sit-ups

10:01 to 15:00 minutes:
Add 20 mountain climbers

15:01 to 20:00 minutes:
Add 50 high knees (left and right equals 1 rep)

Image Source: POPSUGAR Photography / Ericka McConnell

Source: A 20-Minute Circuit That Will Have You on Your Knees : PopSugar