Is Surge appropriate for post-cardio recovery? If not, what is? I've heard chocolate milk. Is that true.
Your answer might depend on your goals. Are you performing cardio for fat loss? Cardiovascular health? Some athletic endeavour?
Either way, I believe that way back when Surge was introduced, initial trials of the formula were tested on competitive cyclists. I have no idea if that article is still around, but the point is that, yes, Surge certainly could be used post-cardio.
If you're training for performance or even if you just incorporate intense interval workouts for body composition, sure. I would not recommend it for low to moderat-intensity cardio.