Ever wonder what those mini-trampolines are used for at the gym?

More videos Ever wonder what those mini-trampolines are used for at the gym?

at the gym
Quite Sure Those Are The Best Tits Ever
At the Gym
At the gym
At The Gym
At the Gym
Those are probably the best titles ever r/JumpyTitsGifs
What are those?!(;
For those that wanted the video i used for the gif
Flashing at the gym :)
Brigitte at the gym
At the gym
At the gym
Ever wonder what the sound sees on the way down?
Flexing at the gym