Hydration

The nutrient you drink

You can eat a perfect diet and still perform badly if you are dehydrated. Water is the nutrient athletes lose fastest and must keep topping up. This module looks at what water does in the body, what happens when you run short, and how to stay hydrated around exercise.

The language of hydration

Four ideas run through this module:

How much to drink

On this course the recommended average daily intake is about 2.5 litres of water for men and about 2 litres for women. That is a baseline for everyday life. During and after exercise, and in hot conditions, an athlete needs to drink more to replace what is lost through sweat.

Match each job of water to what it does

Same two litres, different day

A student drinks almost exactly 2 litres on a rest day and feels fine. She drinks the same 2 litres on a day with two training sessions in hot weather. What is wrong?

• The 2 litre figure is an everyday baseline, and heat and training raise it
• Nothing is wrong, because 2 litres is the recommendation for any day
• She has drunk too much, because exercising lowers the water a body needs
• The figure is meant for training days only, so the rest day was short

Two athletes, same race

The same effort feels very different depending on how well hydrated you are.

When the tank runs low

Select the TWO effects of dehydration on sports performance.

• The heart has to work harder
• Muscle cramps and quicker fatigue
• Faster reactions and sharper focus
• The body cools down more easily

How dehydration takes hold

Put the stages of dehydration during exercise into order.

• The athlete sweats heavily and drinks too little
• Body fluid and blood volume start to fall
• The heart works harder and the body overheats
• Performance drops: cramps, fatigue and poor focus

Match each moment to why you drink then

When you need more

Which situation increases how much fluid an athlete needs?

• A long, hard session in hot weather
• Resting quietly on a cool day
• Sitting still indoors
• Sleeping through the night

Hydration in words

Water helps to _____ the body's temperature through sweating and carries nutrients in the blood. Losing more fluid than you take in is called _____, which makes the heart work harder and can bring on _____ and fatigue. Women are advised to drink a little _____ water each day than men. To perform well, athletes should _____ before, during and after exercise.

Sweat and hydration

Tap the TWO statements that are TRUE.

• Sweating helps cool the body but loses fluid that must be replaced.
• Dehydration makes the heart work harder during exercise.
• Drinking water has no effect on sports performance.
• Men are advised to drink less water each day than women.
• Dehydration improves concentration and reaction time.

Make the fluid call

Decide what each athlete should do about fluid.

• A footballer feels dizzy and starts cramping late in a hot match. What is the most likely cause?
• Preparing for a long endurance race, what should the athlete do about fluid?
• After a hard, sweaty session, what best helps recovery?

Explain and plan

Explain why staying hydrated matters for sports performance, and describe how an athlete should manage their fluid before, during and after a hard session in hot weather.

• Explain two jobs that water does in the body
• Explain how dehydration harms performance
• Describe how to take on fluid before, during and after exercise
• Refer to the recommended daily water intake