Subject: What's the strongest muscle, the heart or the tongue?

I recently had a colleague tell me they had heard on NPR that the strongest 
muscle in the body was the tongue.  What's that all about?  It seems to me 
that the heart must be much stronger--no contest; it works continually your 
whole life.  I mean, just poke a tongue and poke a heart; the heart feels 
much more muscular.  Does it just depend on how you define strongest, like 
a short-term strength versus endurance issue?  Is there anything about the 
heart, like the fact that it is an organ of the circulatory system and not 
like what we normally think of as a muscle, that would keep it from being 
considered a muscle?  I respect the source; NPR is generally pretty 
reliable.  I'm just confused.  What really is the strongest m

Re: What's the strongest muscle, the heart or the tongue?