The deep-work rhythm
The fix
Work in focused ~50–90 min blocks, then take a real break — move, look far, breathe.
Why it happens
Sustained attention runs on a natural ultradian rhythm. Push past it without recovery and blink rate, posture, and alertness all decay together — the physical signature of a fading focus.
If you ignore it
Skipping recovery doesn't buy more output; it trades tomorrow's stamina for today's — the strain compounds night over night.
Wellness & ergonomic guidance, not medical advice.