RFL is a starvation diet. If you're not on an EC stack, you should be lacking energy. The only reason you workout on the RFL diet is to maintain muscle mass. If you are thinking about doing SS, I would recommend you workout 2-3 days/week and possibly cut the volume to 2 sets of 5 reps. And, don't go for crazy linear progression. Keep in mind that the energy for lifting heavy weights comes primarily from glycogen and not fat.