Changes

{{further|Dual core#Mechanism}}

{{further|Dual core#Mechanism}}

{{further|Dual core#Alternative mechanism}}

{{further|Dual core#Alternative mechanism}}

DC1's mechanism is similar to Segmented. Each core sleep is located around each respective sleep peak for efficiency. The first core is around the same length as the first core of Segmented, to preserve the amount of SWS, while the second core is cut short. This allows for sleep reduction on the schedule.  

DC1's mechanism is similar to Segmented. Each core sleep is located around each respective sleep peak for efficiency. The first core is around the same length as the first core of Segmented, to preserve the amount of [[wikipedia:Slow-wave_sleep|SWS]], while the second core is cut short. This allows for sleep reduction on the schedule.  

Currently the standard variant is recommended to have a core sleep of 3h20m and 1h40m respectively. The cycle length being a multiple of 100m instead of 90m is meant to accommodate either longer sleep cycles, or extra REM at the start or the end of the sleeps.

Currently, the standard variant is recommended to have a core sleep of 3h20m and 1h40m respectively. The cycle length being a multiple of 100m instead of 90m is meant to accommodate either longer sleep cycles, or extra [[wikipedia:Rapid_eye_movement_sleep|REM]] at the start or the end of the sleeps.

The nap is placed around the circadian dip  in the early afternoon. However, the nap on DC1 is not always filled with REM sleep and may contain mostly NREM2 for some. Nevertheless, the nap helps [[wake time reduction|sustain alertness]] until core 1.  

The nap is placed around the circadian dip  in the early afternoon. However, the nap on DC1 is not always filled with REM sleep and may contain mostly NREM2 for some. Nevertheless, the nap helps [[wake time reduction|sustain alertness]] until core 1.