They're grammatically correct, but neither idiom is quite right.
I don't understand the first sentence. It isn't clear what you mean by 'get a blow'.
It's possible to say that someone 'ran for HIS dear life', if, for example, he was being chased by a tiger and feared for his life. It's not an expression that is used very often, though, and you wouldn't normally use it if you are talking about a race.