Technically…any window works. And what you can stick with is best. Personally…im a fan of cycling my window around, but minimize eating late. There are is enough research to support that the most ideal thong is to have food digested before you go to bed…and that’s generally a minimum of 4 hours…minimum
I’ve been doing IF for many years. I’m a short female lol but I’ll share my opinion.
I feel that it’s best to stop eating well before bedtime. Because our bodies are supposed to regenerate our cells during sleep. I think digestion can sort of interfere with optimal cell regeneration.
I do not focus on calories but rather focus on carbs. I try to keep my carbs as low as possible but realistically I get about 50 - 70 carbs a day. Sometimes much less, sometimes more. I eat healthy fats, veggies, a bit of dairy such as cottage cheese with probiotics, a bit of fruit like a grapefruit, and a bit of protein. A few pieces of dark chocolate squares and or a small handful of dark chocolate covered almonds. So basically I do keto and IF. I have keto strips that I use when I’m really focused on losing.
I also try to exercise during my fast because I feel it makes a difference. But I don’t need to exercise in order to lose weight. For example I’ve had plantar fasciitis earlier this year and recently a knee injury and have not been able to do my vigorous walking routine but yet I am still losing.