Michelle was reading a book called Complications that mentions an experiment to test your pain threshold. It involves filling a bowl with room temperature water and another with ice water. You put your hand into the room temperature water for 20 seconds and then shift it to the ice water. With a stopwatch (preferably someone else is timing it) you report when you first feel some pain. This is your threshold. Then you keep your hand in as long as you can stand, up to two minutes. Across people, the pain threshold is pretty similar, but the time it takes before you simply can't stand it anymore varies widely.
In our trial tonight I lasted the full 2 minutes but felt pain at around 6-9 seconds. The amount of discomfort was surprising actually. My wrist felt like it was kinking up. Michelle went to 24 seconds, but after her bridge work she still has some residual pain that probably affected her "score". The average, according to the Outside article, is about 20 seconds.