Schedules · Experienced · 4 h window
20:4 · Warrior
A 20-hour fast with a four-hour window, usually one substantial meal and something smaller. The window is short enough that it takes some planning around other people.
One example day
Eat between 16:00 and 20:00, then fast 20 hours until 16:00 the next day. Any window that fits your day works the same way.
The phases a 20-hour fast reaches
- 0 hBlood sugar settlesDigestion finishes; most notice nothing
- 4 hStored glucose declinesHunger comes in waves
- 8 hFat burningMore fuel drawn from stored fat
- 14 hKetosisKetone use increases; onset varies widely
- 18 hAutophagy signallingStudied mostly outside everyday conditions
The fast ends in autophagy signalling. What happens at 20 hours
20:4 · Warrior is one of the app’s presets. Set it as a routine with a reminder before each fast.