Possible Clues:

• Exercise pressure preceding spasm of digestion
• Vigour and twitching in the digestive system
• Closely related to 36 across in picture capturing record time
• Spirit given sudden shake is good for digestion
• -- ulcer, ulcer of the stomach
• Concerned with digestion? Go getting nervous reaction
• Epic novel about heartless Irishman might be hard to digest?
• Pertaining to digestion
• Exercises twice before unwrapping rich digestive
• Digestive spasm following fizz