I modelled these for some animation practice.
The blend contains the following low poly gymnastics equipment.
Asymetric bars - rigged with shape key drivers
Parallel bars - rigged with shape key drivers
High bar - rigged with shape key drivers
Rings - sorry not rigged
Springboard - springs and board both rigged with shape key drivers
I've tried to keep the scale as accurate as possible (1BU = 1m)
You can view a short animation I did below.
Have fun with them, comments are always welcomed.