110%: Is it really possible?

Why do coaches always tell their players to give 110%? If I'm as smart as some people think I am, then wouldn't that mean death? I'm pretty sure coaches don't want to literally kill their players, so they shouldn't keep repeating that cliche. I mean, a hundred percent is all you got. Anymore and you would kill yourself. 

You're probably thinking that 110% is possible. What's this girl talking about? Everybody can push themselves beyond their limits. Duh. If you try your hardest and do something that you weren't able to do before, you're simply giving a hundred percent. You can improve, so each time you give your hundred percent, you get more out of it. Maybe you weren't giving a hundred percent before. Once you do give a hundred percent of heart and effort, you'll be lead to think that you were giving 110%. I hope I didn't confuse you. 

Coaches tell their players to give 110% to motivate them to do better. The thing I want to know is this: why 110%? Why do coaches use that particular number? If you really want to stress that your players should give it their all, then why not use 1,000,000%? Or maybe even an infinite percent. 

Things like this just give me something to think about while I'm doing a test or something.

Caution: Don't give 110% in trying to understand this. You may put yourself into a mental lapse or a coma.