Related Clues:

• Marathoner's concern
• Throe
• Writer's cramp, for example
• Flurry of activity
• Quirky behavior
• The first O of O-O-O
• Charley horse
• Muscle woe
• One might be verbal
• Seizure
• Involuntary contraction
• First O of O-O-O
• First correct Hollywood Square
• Charley horse, e.g.
• Back ailment