Historical clue formulations

• *Simple exercise [Opposite of 16-Across?] — 2024-01-02
• Ab-toning exercise — 2022-12-13
• Exercise that targets the 9-Down — 2020-05-05
• Exercise bit — 2015-08-07
• Abs worker — 2014-04-09
• Exercise unit — 2014-01-28
• Rise partly — 2008-01-19
• Stomach strengthener — 2007-05-08
• Show sudden interest — 2006-09-23
• Crunch — 2003-07-10
• Exercise for the abs — 2003-06-09
• Exercise unit — 2002-01-23
• Get out of a slump? — 2001-08-16
• Ab strengthener — 2001-04-16
• Take notice — 2001-01-30
• Exercise unit — 2000-05-12
• Exercise unit — 1998-12-25
• Ab strengthener — 1998-10-27
• Stomach tightener — 1998-08-07