pile on the pounds
To put on weight quickly, especially a large or excessive amount. Wow, Jim really piled on the pounds on while he was on his sabbatical. I'm trying to pile on the pounds so I can make it on the football team this fall!
pile Pelion on Ossa
1. To further complicate something that is already tedious or challenging. Ossa and Pelion are two mountains in Greece. A: "I told Becky you would pick her up." B: "I already have so much to do today—quit piling Pelion on Ossa!" Just when I thought I was almost done sorting these files, my boss piled Pelion on Ossa and brought me another box of them.
2. To do something that seems futile. I know that I'm just piling Pelion on Ossa by telling you to stay away from that boy, but I'm your father, and I don't want to see you get hurt. That couch will never fit up the steps—tell them to stop piling Pelion on Ossa!