FWIW, and it might not be worth much, the only consistent effect I have noticed in this regard has to do with state-dependent memory.

That is, when sitting for your exam, do your best to put yourself in a physical state that matches the state in which you generally study. So, for example, if you go for a run before you you study, do the same before you take the exam. This, btw, may have something to do with the study to which you link.

Alternatively, if you are generally sedentary and strung out on caffeine while you study because you are cramming, stay sedentary and strung-out on caffeine until you take the exam.

NOTE: I have no opinion on the more narrow question of "What is the best exercise regimen to optimize studying and exam-taking."

I dont consider exercising on a exam's day. I do exercice. :D

I've experimented with it first about 2 months ago. I was studying for about 5 days in a row, done my notes, read papers, conclusions, abstracts, another classmate notes, various presentations and powerpoint. I was so full of it, so anxious and mentally foggy, that i decided to grab my chalk and my deadlift slippers and went straight of to some heavy lifting.

1 hour after, i was clear minded, happy and energized. I ate a big and nice meal and went off to do the exam. My pen just flowed, i finished first(which can be a little awkuard) but i felt fine and get a good mark. Last week i did the same, went awsome too, im expecting a good mark again. ;)

I was tempted to try fasting on the day of my exam because of how much sharper I sometimes feel but I don't really want to risk it in case it goes wrong so I just eat bacon eggs some sweet potato and a coffee instead! Another tip that apparently works is to have a particular smell like peppermint while you're revising, then take some in to the exam and smell it and apparently you will remember loads more once you smell it!

I stopped studying for my nursing license exam and spent my week working and relaxing. The day before I sat for my exam I ate lots of dark chocolate, swam and made lots of maritals. I passed with a minimal of 85 questions so it's all good haha. I always feel better after bike ride to work. My memory is sticker and I have endorphin high that lasts for most of the shift.