I've done anywhere from 5 to 10 iu. on different occassions. It was done 2-3 times in one day, never did it with every meal during the carb up. I preferred 6-8 iu done 4-6 hrs. apart, the day before pre-judging. With slin, i can carb up enough on just that one day. I think you have to consider your size and how depleted you are, to determine how much and how long to do it. Honestly, half a day is good for me with a shitload.