Your nutrition questions answered ✅ You sent us a tonne of questions about marathon nutrition. We put them to the experts at Science in Sport—here’s what you need to know ⬇️ ❓Is there a max amount of caffeine I can have on race day (including my morning coffee)? Caffeine can be a great tool to pick you up mid-race but you should aim to stay under 300–400mg in total. Remember to check your gels (e.g. SiS GO Energy Cola Gel = 75mg), and don’t forget your morning brew counts too! Caffeine kicks in