From what I was able to find, it's a wresting term. Going from what I have found that Nuclear Heat is when the audience more or less has to be physically restrained from jumping the guardrails, which doesn’t happen often anymore.

You would be correct. Though nuclear heat can also be outright verbal and not just physical. Basically it means that the heel (bad guy) did or said something that really pisses people off, the fans specifically.

This has been your local wrestling nerd's lesson of the day.

Oh yeah. I meant to ask this earlier but it totally slipped my mind. Is there anywhere one can watch these things subbed? Or I guess the question is, has any group ever subbed these?

Yes, yes there is a place you can watch them subbed. I know of two places actually.

Check out OverTime and TvNihon. Those usually have all you need.

I use Henshin Fever and kissasian.com

Looking it up on Henshin Fever it looks like they only have the raws, I have looked at OT and TVN's pages but I didn't find anything...anyone have links?

Go to kissasian.com and look it up.

I did, they don't have these shorts. Or at the least I could not find them.

Weird, someone has definitely subbed them though because I have them (I just don't have access to my HD right now to tell you who). I can only assume TVN have them thrown into a batch somewhere - did you go through those?