Watching the cycling classics and the distance they race is incredible. The fuel/ type of nutrition and frequency they have to take on board is so important. This transfers over to long distance distance triathlon.
Test out your nutrition during your training and check out what the organisers are providing on race day. Some types of nutrition can have an impact on your stomach. Many leading nutrition companies have intro packs so worth while going down that route to begin with.
All good preparation- the bike is the most important for long distance riding and pacing yourself from the start and that means the swim as well as the bike.
The weather is changing as well we all know and this again can have a huge impact. Check where you are racing / what is available that you have enough nutrition with you as the local shop may not stock what you need.
Moving up a distance: my son Tom Bishop has finally moved away from the Triathlon World Series and is competing in long distance triathlon. He is now having to think very differently about fuelling differently. It’s like a new lease of life for him and very exciting. Lots of rookie mistakes ‘even for a pro’ in his first season but now beginning to reap the rewards.