36 hours fasting
In this form, you do not eat for 36 hours at a stretch. Then, for example, you eat dinner at 7 p.m. on Monday and may not eat breakfast again until 7 a.m. on Wednesday. Then you have fasted for 36 hours, and you do this one time per week.
This scheme is suitable for burning a lot of fat in a short time but is not for fasting beginners.