[tuesdayrain]

Well, it was obvious to me when I started dry-heaving after going on a morning run without eating first. It was a distance/pace that I never found particularly challenging under normal conditions. It's interesting that other people seem to have no problem exercising on an empty stomach.

[foldr]

If you're not used to it it might feel weird. But you absolutely can do intense exercise without eating first.

[erikpukinskis]

Does your dry heaving mean anything other than you were feeling stress? Or that your abdominal neurons were disoriented?