I think you may be overtraining a bit. Mark recommends 2 days a week of lifting plus one sprint session and lots of low level movement like walking, swimming, or easy bike riding. Sometimes less is more.
I highly recommend the book "Eat Stop Eat" by Brad Pilon for pointers about IFing. I don't think it has to be on any set schedule. Sometimes I jsut don't feel like eating so I don't.