I have done this a lot and I am still doing it.
Great for core strength and hand strikes, and once your core is powerful, it will help with kicking as well.
It even helps with breathing, yeah I know, that sounds weird, but it really does, I will talk about it.
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As a professional fighter, one of his favorite tactics was the liver shot (both punch and kick), and he popularized its use in MMA. Bas is known for his charisma and has capitalized on his celebrity status since retiring from fighting in 1999. He works as a color commentator in the MMA orginazation. He has appeared in numerous tv shows, movies, and video games. He also coaches MMA and has authored several instructional materials.
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