It's good to have banana before running but...
banana castella is good for "breakfast" on a race day。
It won Gold medal at Himeji Sweet Expo.
The reason why I wrote "breakfast" because if you have those sweets right before a start, the blood sugar level goes up too high, insulin is produced to make it lower, and there is a risk of to become a low sugar syndrome instead. It's also called "daifuku rice cake* syndrome."
* a rice cake stuffed with red bean paste.