Related Clues:

• Back twinge
• Sudden muscle contraction
• Involuntary muscle action
• Cramp, say
• Email blitz overwhelms son in sudden attack
• Hiccup, for one
• Muscle cramp, e.g
• Knee jerk, perhaps
• Cause of a hiccup
• Hiccup, for example
• Flash of energy
• Sudden jerk, head on mattress touching springs
• Lessening
• Weight loss, say, from period of psychiatry?
• Cause of writer's cramp, often