1.0 link Rainbow Dash Network http://rainbowdash.net/ Logan (circuithooves) http://rainbowdash.net/circuithooves http://rainbowdash.net/notice/3037668 @<span class="vcard"><a href="http://rainbowdash.net/user/60" class="url" title="Scribus Caballus"><span class="fn nickname">scribus</span></a></span> First off. It requires precise timing as the heart rate plays a key factor. not to mention force of blow. these are the factors that could ultimately make the difference in producing a cardiac arrest from a blow to the chest.