There are more ways to do pushups than just about any other exercise, which means your mind and muscles will never get bored.

But if you need some inspiration for your arsenal, check out these two up-and-down pushup workouts from Men’s Health Fitness Director B.J. Gaddour.

Related: 22 New Ways to Crush Your Core

They work your chest, shoulders, and arms, but they also hammer your abs. That's because they reduce your stability, forcing every muscle from your shoulders to your hips to "turn on" the entire time. Watch Gaddour demonstrate both in the video above.

Challenge One
Assume a pushup position on the floor with your feet a couple inches in front of a bench. Perform a pushup. When you push yourself back up to the starting position, pause with your arms straight.

Now place both feet on the bench. Do a decline pushup. Pause at the top, and bring both feet back down to the floor. Alternate between a floor pushup and a decline pushup, performing as many reps as you can without stopping.

Challenge Two
Assume a pushup position on the floor with a bench in front of you. Place your hands on the floor so that they're about two feet from the bench. Do a pushup, and pause after you push yourself back up to the top.

Related: 10 Ways to Make Your Pushup Better

Without letting your back sag, reach your left hand straight out in front of you so it’s on top of the bench. Do the same with your right hand. You should now be in an extended plank position with your body creating a straight line from hands to heels.

"Walk" your feet forward toward the bench until your hands are directly underneath your shoulders. Pause, and then perform a pushup on the bench. Walk your feet back until you are in an extended plank position again. Lower your hands one at a time to the floor, and perform another pushup.

Repeat this pattern, performing as many reps as you can without resting.

More Men's Health:
-- The Lunge That Smokes Your Hips and Thighs
-- 23 Best Biceps Exercises
-- 11 Women Who Prove Smart Is Sexy
-- The J.J. Watt Workout