Related Clues:
- When they're ripped, they're strong
- Muscles in sit-ups, informally
- Muscular sextet
- Midriff muscles, for short
- Nuclear center?
- Ones demonstrating strength in crunch time?
- Targets of plank exercises
- Old Republican seen in church centre
- Muscles strengthened by Pilates
- They're strengthened by crunches
- They may get crunched during exercise
- Reactor meltdown site
- Bosc center
- Tactical unit, reportedly essential element
- Core workout target