Some parts of training are meant to feel challenging. Your breathing may become faster, your muscles may feel tired and you might need to concentrate more to hold your technique. A set feeling hard does not always mean that something is wrong. Your coach may be asking you to practise maintaining a skill, pace or effort when you are becoming tired.

Most children aged 6 to 12 are recommended to have 9 to 12 hours of sleep during each 24 hours. Teenagers aged 13 to 18 are usually recommended to have 8 to 10 hours. These are ranges rather than a perfect number for everyone. One swimmer may feel rested with a little less than another. Growing, training, illness and a busy week can also affect how tired you feel.

Sleep is not just time when you are doing nothing. While you sleep, your body is recovering and your brain is helping you remember what you have learned. This matters for swimmers because training uses both your body and your mind. You need energy to complete the session, concentration to listen and coordination to practise skills correctly.

Your body needs water to work properly. During swimming, you lose some water through breathing and sweating. You may not notice yourself sweating because you are already wet and the pool helps keep you cool. Being in water does not mean you cannot become thirsty or dehydrated. Not drinking enough can make it harder to concentrate and train well. You may also feel thirsty, tired, dizzy or develop a headache. Tell your coach if you feel unwell during a session.

Before training, you may have been sitting at school, travelling in the car or waiting beside the pool. A pre-pool warm-up helps your body and mind change from resting to being ready to swim. The movements gradually raise your body temperature and prepare the muscles and joints you will use in the water. They can also help you focus on the session ahead.