Mahjong stamina

Going for a two-day Riichi Mahjong tournament, and I'm terrified of my stamina. Can barely survive 3 hanchans back-to-back. It's okay if I don't use my perfectionist method of card-counting every hanchan, I suppose. But I'd rather get used to tile counting for better games.

Some tips for lasting longer in tournaments:

• Get a good night's sleep
• Healthy diet
• Stay hydrated
• Eliminate distractions
• Good posture
• Avoid stimulants, especially caffeine
• Make the most out of your breaks
• Dress for comfort
• Stay curious, stay hungry
• For girls: pin your hair back comfortably
• Prepare some eye drops if you're prone to dry eyes