Get a marathoner,take him to a boxing instructor,give him crash
boxing training and make him/her work out on the bag at the speed
and movement of,say an advanced boxer,asked how he/she felt?
15R of boxing is very tired,despite what people believe.
And you think Mike Tyson is just using brute strength? Do you know
the staple training of boxing?
I remember my boss talks to me about martial art and kind of
similiar sports. He said: u might be light weight, running around
like monkey and a black belt in martial art. But i outweigh you by
so much. U might have the reflex to punch me 10 times and escape
all my punches, if u get one of my punch thorugh...for sure you
aint going to wake up from it. Get the logic. 
BB's value nowadays is so diluted that it is pretty useless.Get
over it.
However it is true that one with heavier weight would win a
fight,provided that both their skills are more or less equal.What
MA your boss took btw?
Just for your info,Mirko "Cro Cop" KOed Kimbo in K-1,and Kimbo is
double the weight of Mirko!!! And a sanda fighter beat the shit out
of the sumo wrestler ,who is 3 times the weight,too~~~
each sports has its merit. 
Most
folks will think that they are very fit because they spent maybe 7
days a week practising it. But they aren't even top 10-20% of the
top notch in their sports and yet claim that they are very fit.
True,considering both amateur and professional.
A commando or runner claims that he can run 7mins in 2.4km does it
means he is very fit? Alas, most mortal will claims that he/she is.
[/b]
A commando is not meant just to run,so you have to compare to
other commandos,or soldiers.
