Fig 1. Changes in Sleep Debt by hour across the 3-week (twelve 42.85-h “days”) Forced Desynchrony protocol.

Sleep Debt in the Control group varies around zero hours due to prolonged wake and sleep bouts with a 1:2 sleep:wake ratio. The Chronic Sleep Restriction (CSR) protocol accumulates Sleep Debt across the entire duration of the protocol. Heavy lines indicate when the sleep was scheduled.