I think the Vacuum Sucked Up Her Waist

vintagefit vacuum image

The slim silhouette is not just on the Hoover vacuum.  Look at her hand. Look at her waist.  Her waist and her hand are the same size!

I am 99% sure the ad agency graphics guys were all male.

She looks like she is having fun jumping around the house with her Hoover. But I can think of better ways to work out.