If you’re not mobile, you can’t use your strength. And if you’re not strong, you can’t be mobile, says David Jack, owner of ActivPrayer in Phoenix, Arizona, and co-creator of the Men’s Health Body Battle.

That’s why Jack includes the downward dog to crab reach in his routine. It simultaneously improves your strength and mobility. If you’re inclined to roll your eyes at exercises like this, just give it a try. You may find it challenges you in ways you didn’t expect. 

That’s because downward dog demands flexibility and mobility along the backside of your body, and strength from your chest, arms, and shoulders. The crab reach loosens the front of your body, while relying your glutes, hamstrings, and shoulders to hold you up.

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Watch the video above to learn how to perform the downward dog to crab reach with perfect form.