There’s a sickness that goes with sleeping three hours a night, a week at a time. It’s nausea, or actual vomiting, diarrhea, abdominal pain; headaches that border on migraines. Your joints ache; your muscles are tight, especially through the shoulders; your vision is blurry. Sometimes you see double. Food tastes odd. Your hands shake. Sometimes your whole body shivers. You drop things, you trip over things. Periodically, your heart races with no apparent provocation.
If you told me for a fact I would never sleep more than three hours a night for the rest of my life, I would kill myself, and it would be a perfectly rational decision.