What if you could achieve an hour's worth of workout results in just five minutes? It's not easy, but it is possible. My five-minute core workout routine requires no machines, no weights, and no personal trainer. Rotating just two very easy-to-master exercises for five minutes five times a week will result in core strength that will emanate throughout your entire body. You'll get tighter abs, defined buttocks, and a stronger upper body. Here's how it works:

Start in plank or push-up position with your wrists directly under your shoulders. Lift one foot off the ground and bring your knee to your chest, contracting your stomach in the process. Then repeat with the other knee. Continue to alternate as fast as safely possible for 30 seconds.

Lie on your back and contract your abdominal muscles so your shoulders are slightly lifted off the ground. Place your hands behind your head and contract your abs so your right knee meets your left elbow, then switch to the other side. Keep alternating sides until you've completed as many of these crunches as possible in a 30 second window.

Switch between the Mountain Climber Crunches and the Biker Racer Crunches, doing each for 30 seconds until you've reached a total of five minutes—that means each exercise five times.

If at first this routine is too difficult, start smaller. Begin with 10 or 20 second increments and work your way up over the next several weeks.  Soon enough, you'll have the strong, defined core you've always wanted…and plenty of extra time to flaunt it.

(WATCH the video above to see how it's done)

David Sandoval is the founder of Purium Health Products and author of The Green Foods Bible. Learn more at puriumcorp.com. 

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