strenuously, with great vigour, strongly, powerfully, potently, forcefully, with force, forcibly, energetically, aggressively, heartily, eagerly, with eagerness, enthusiastically, with enthusiasm, with great effort, with all one's might, with might and main, with a will, for dear life, for all one is worth, to the best of one's abilities, as best one can, all out, with a vengeance, fiercely, intensely, hard, as hard as possible, as hard as one can, with all the stops out, like the devil, like the deuce, at full tilt

informal like mad, like crazy, like nobody's business, like it's going out of style, like billy-o, hammer and tongs, going great guns