Swimmer Diana Nyad -- Barack & Michelle Obama Are My 'Homies' Now!

American swimming legend Diana Nyad finally returned home to L.A. last night after her historic Cuba to Florida swim ... and told TMZ she got some new "homies" after the feat ... Barack and Michelle Obama.

The 64-year-old ultra-athlete received a hero's welcome when she arrived at LAX (balloons, kazoos, posters) ... and of course, we needed to know one thing -- how much did she pee out there??

Nyad's answer --well, let's just say she may have raised the water table in the Atlantic.

Diana also told us about how she stayed safe from possible shark attacks. Interesting stuff.

Bottom line -- Diana's a friggin' STUD.