Go to the gym, turn the treadmill up to full speed and jump onto it, and see how it goes. That'll be a good data based test. The mill will drop speed by about 30% and most mills don't go up super high. Take a face plant for science.

If you did then you're probbably faster than normal and better balance than normal. I'm pretty sure I'd pull a hammy immediately. My coworker immediately face planted and broke arm and collar bone.