Possible Clues:

• See 43-Across
• Pasta or potatoes, to an athlete
• In short, engine part�s source of energy
• ___ up (have a pre-marathon meal)
• Nutrition unit in pasta, informally
• Consumer's energy source, informally
• Dietary unit, for short
• Diet no-no, often
• Potato or pasta
• Pasta, e.g