Groin muscle cramping

When I go from the bike to the run, both groin muscles cramp up. It’s happened in both of my last two races, and in each brick workout for the past 6 months. Any ideas? Thanks.

Let’s run through the standard answers:

  1. Bike fit? - I had this exact problem several years ago and getting a good fit fixed it.
  2. Proper hydration/sodium balance?