What word (adverb, preferably) can we use to show that we need to study harder and cover more stuff than usual in a short amount of time?

"We need to study ___________(ly) in order to not fall behind."

Being a non-native speaker, I’m thinking of the words "compactly" and "compressedly" (whose translations are exactly what we use in Farsi in such situations). But I don’t think those would be natural-sounding in English.

Edit: Obviously, "hard" wouldn’t fit well there since it doesn’t emphasize "a lot of stuff in a short amount of time"