Possible Clues:

• It's invigorating to catch king out
• it needs something heavy,I see, to give one a lift
• Nervine, for one
• Perhaps might begin with it for weight, I see
• Type of water
• G, in with it!
• Gin mixer - pick-me-up
• It'll buck you up with a little gin in it and give you weight, I see
• Muscular spasm stopped by dealing with a shot in the arm
• Accompaniment to gin?