You will need the MESH_ju-beos_slimbb-overalls060311 mesh from
here for these to show up in your game.
Here is my take/conversion of the Nightlife raver outfits for the slimmer bodybuilder (Nightlife is NOT required for these, they should work with any version of the sims game).
There are 8 outfits organised into 2 sets with 4 outfits in each set.
Set 1.
Set 2.
Credits:
Mesh - Marvine and Beosboxboy