I recently read of a techinque that one of the guys from the Jackass movies uses. Jackass of course is a series of movies featuring a bunch of guys doing stuff that nobody should ever do and generally acting like jackasses.
This is hard to do, mentally, because of course when you’re in the shopping cart facing the giant ramp, all of your instincts scream at you not to launch yourself down that sucker. One of the guys (I forget which one, and googling for this is hard - as always if your google-fu is better than mine, please let me know and I’ll give credit here) has a strategy - he simply counts from 5 to 1, and then does whatever it is.
It’s a stoic technique. It gives you a chance to actually feel your fear, while still giving you a reason to take action.
It’s not a cure-all, of course, and it takes a particular kind of cold blood to take the plunge when you’re done counting. But it’d get easier with practice, and it’s a kind of bargain with your emotions. It means that you get to have it both ways.