You will need the boardshorts mesh for the bodybuilder from
here for these to show up in your game.
Here are 24 re-colours of the boardshorts mesh for the bodybuilder.
They are organised into 6 sets with 4 items in each set.
Set 1.
Set 2.
Set 3.
Set 4.
Set 5.
Set 6.
Credits:
Mesh - Marvine and Beosboxboy