Why Can't I Float? Understanding Buoyancy and Body Composition

Question
Hello,

I am very sad to have to ask you this question.  My girlfriend and I got into an argument about whether or not I can float.  I could float when I was younger, so I know how to, but I just can't now.  I work out a lot but don't eat much and my percent body fat is between 3 and 5, closer to 3.6%.  Could you please let her in on how much denser I am because of this....and that I just may not be able to float?  But mayble I'm wrong...Thanks  EG--

Answer
Erik--
Don't be sad,you are correct. The reason that people float ia their body fat composition.  People with a low body fat comp. will not be able to float as easily as people with a higher comp.  Women tend to float easier because even a physically fit woman has a normal body fat percentage between 14 to 19%.  This is normal.  A normal healthy male only has between 8 and 12% body fat.  The more muscular you are the less subcutaneous(under the skin) fat you have.  
I hope this answers your question.
George