Getting in shape can be a maddening thing.

You sweat your butt off regularly on the treadmill and at Pilates. Only to find that, in fact, your butt looks exactly the same.

It’s enough to make you want to punch someone.

So go ahead — at the new Ring Boxing Club, where old-school boxing and new-school workouts collide. Beginners are welcome, as are ladies — almost 40 percent of the Club’s members are women.

Each session puts you through the paces as if you were a real professional boxer (you punch the heavy bag and the speedbag, you shadowbox, and you even spar, should you feel so inclined) and is taught by a certified boxing coach. You burn ridiculous amounts of calories and tone up fast. (You don’t think Hilary Swank was born like that, do you?)

What’s more, you also learn self-defense.

So instead of having a bad ass, you’ll be one.

The Ring Boxing Club, 971 Commonwealth Avenue, second floor (617-782-6946 or ringboxingclub.com).