I find that I can naturally do 24 hours but afterwards I want to cave.
My goal is to fast for one week a month
No idea what will work for you but I did a week of rolling 24hrs with 1 large meal before restarting, then the same with 36s and then two 72s, I only went to 6 days as my daughter needed an operation on day 7 but it wouldn’t of been difficult to get to 7 days
Well, here’s my method.
Step 1) do a 1 day fast. refeed.
Step 2) do a 2 day fast. refeed.
Step 3) do a 3 day fast. refeed.
Step 4) do a 4 day fast. refeed.
Step 5) do a 5 day fast. refeed.
Step 6) do a 6 day fast. refeed.
Step 7) do a 7 day fast. refeed.