Related Clues:

• Stomach muscles, briefly
• Granny Smith throwaway
• Pecs neighbors
• Nucleus
• Center of an apple
• Apple's leftover
• Fundamental
• Essential part
• They may be ripped
• Gym rat's six-pack
• Hunk's pride
• Core group?
• Targets of crunches
• Situps' target
• They may be crunched in a gym