Nutrition and hydration are key to training and racing well day in / day out. If you fuel your body in the right way this will assist training performance and recovery as well as increase performance at competition.
Take a read through these documents to guide your nutritional intake:
(thank you to Swim England and British Swimming for the documents)
Have a look at these videos below to understand your nutrition more:
Nutrition at home / Nutrition to maintain
Practical Nutrition advice for swimmers