The whistle blows, your head is pounding, mouth is dry, and you’re breathless. You know what you need. Instinctively you run toward the side of the pitch, because there it is, perched on the bench; icy, inviting and irresistible – the water bottle. What makes it so special?
Did you know that your body has 35-45 litres (9-12 gallons) of water? This body water can comprise up to 80% of your body weight during adolescence. Staying hydrated means maintaining your body water levels, and is achieved by drinking when thirsty. It’s something that our Fuel My Potential athlete Joseph Schooling takes very seriously. Literally the first thing he does every morning before swim training is slug 500 mL (17 fl oz) of water. He knows that keeping well hydrated really helps him deliver at those precious training sessions.
Our body monitors our water levels carefully through special receptors in the brain and throughout our body. A dehydrated cell is an unhappy cell. Every organ, tissue and cell in our body requires water to function optimally. All day water allows chemical reactions to occur making sure our body temperature is just right and maintaining our blood volume. Water also acts as a cushion, protecting our joints and spine from damage, as well as playing an important role in our waste removal system.
How much fluid do you need?
Every day, we lose around 2.5 L (85 fl oz) of water in our urine, sweat, faeces, and from our breath. Have you ever seen your breath “steam” in the cold? This is a visible sign of moisture leaving your body. We replace our water losses by drinking fluid, eating food and from within our body itself. Solid food provides us with up to 1 L of water a day (34 fl oz), while chemical reactions inside our cells produce an extra 400 mL (14 fl oz) of “metabolic” water. The rest is replaced with the fluid we drink. Adolescents in the US are recommended to drink around 3 L per day for males, and 2 L per day for females.
The effect of exercise on hydration
It is easier to keep our body water optimal in our day-to-day normal lives. But, when we begin to exercise it is a different story. We lose more water through all the sweating and heavy breathing we do with exercise, making hydration even more important. During exercise we breathe deeper and faster in an attempt to get more oxygen in and get all the carbon dioxide our body is producing out via our lungs. All of this extra breathing results in more fluid loss.
Did you know it is quite common to weigh less after exercise than before? Usually it’s by 1-2 kg (2-4 lb). Most of this weight loss is body water. If it is not replaced it can have body sapping consequences, which are worsened in any hot environments. Dehydration during exercise can affect performance, causing us to become lightheaded, dizzy and fatigued. If you don’t replace this fluid during recovery after exercise, it can also impact how you feel for the rest of the day.
How can you keep well hydrated?
As an athlete you can give yourself an edge in both training and competition by being aware of your own signs of dehydration and acting on them. Joseph Schooling is particularly good at this. For example, you may begin to notice that your mouth becomes dry and your heartbeat quickens, or you start thinking about water. These are cues to reach for your water bottle. Sometimes you can replace fluid while you train, with regular short drinks breaks between sets or breaks in play. Sometimes it is harder to drink enough water during training and competition. Therefore it is really important that you turn up to training or events well-hydrated, having drunk plenty of water over the days before. Fluid is something we all instinctively reach for after exercise, but you can only hydrate if you have a water bottle with you, so make sure you are well prepared.
What should you drink?
Because our body is made up mainly of water, this is the best hydration beverage. Even a sports drink, with its carbohydrate and electrolytes, is mostly water. Which drink you need depends on how often you train in a week, how long each exercise session is, how hot it is and what you have eaten. Sports drinks contain carbohydrates and electrolytes, which also come in many foods we eat. These beverages can sometimes be useful for sporting events of long duration or over tournaments. This is because drinking the electrolytes like sodium and potassium with water can help to draw water deeper into the body when your hydration status is really being challenged by hours of exercise.
So, whether you are lounging around watching Netflix or training hard on the field, track, or in the pool, look out for signs of dehydration and endeavour to develop this skill just as Joseph has. Make it a priority to always keep an icy, inviting and irresistible bottle of water on hand for that sneaky sip.