User blog comment:B214/Question and Answers 2/@comment-86.81.216.93-20140530081009/@comment-1359322-20140530081425

No Issei can't boost his power permanently, he needs to reset the boosted power otherwise the burden would be unbearable on the body, plus it consumes too much stamina. Also you can just use the reply button if you are going to ask on the same topic as your previous topic.