Board Thread:Theories and Speculation/@comment-27162446-20151208003121/@comment-3965545-20160114194256

As shown with Tsunade it can run out too and it doesn't last long. Madara damn near killed her not long after Naruto left to fight Rinnegan Obito and I am certain Tsunade has MUCH more chakra then Sakura, even if it is easier for Sakura to maintain it since she is young.