The Importance of Good Nutrition & Hydration For Being Active

What’s the importance of staying hydrated during exercise?

Exercising without water is like hiking without boots or running without trainers- it’s simply not conducive to an effective workout. Water is essential for maintaining blood volume, regulating body temperature and allowing muscles to contract properly. This is why, when discussing the importance of good nutrition and hydration for being active, at the top of our list is the importance of hydrating before, during and after exercise. 

When you are dehydrated, your body will have reduced blood volume and less fluid available to create sweat. Your body’s capacity to deliver oxygen to your muscles will be reduced and the ability to regulate body temperature will be decreased. As a result, your capacity to perform exercise will be hindered, and your perception of how tough the workout feels is likely to be elevated. 

Instead, by keeping hydrated your body will be able to perform at its best level. Continuing to top up your fluid intakes throughout exercise will replace the fluids lost in sweat, thereby preventing dehydration. Once you’ve finished exercising, continue to top up on fluids. The number of fluids you will need to intake will depend on how much fluid you lost during exercise. This can be calculated by comparing your pre and post-exercise bodyweight. 

Don’t overdo it...

Although you might not think it, avoiding overhydration is also key to the importance of good nutrition and hydration when it comes to physical activity. Preventing dehydration by taking on fluids is key, however, the effects of overhydration (or 'water intoxication') can be just as damaging. Overhydration reduces the amount of sodium in your blood and can make you feel tired and nauseous.  To avoid this, you want to make sure you’re drinking at a rate that is compatible with your body’s level of sweat loss. If the temperature is relatively cool and the exercise you are doing is moderate, the number of fluids you intake will need to be a lot lower than if you’re doing an intense workout in a hot environment.  A good tip to avoid overhydration is to take frequent but small water breaks rather than drinking a gallon of water in one go at the end of your workout. 

What about nutrition?

Fuel your body so that you can perform at your best. When discussing the importance of good nutrition and hydration in exercise, there are 2 main food groups we need to focus on. These are carbohydrates and protein. Eating the correct amount of carbs and protein as part of a balanced diet is essential to providing your body with the fuel it needs for exercise. 


Carbohydrates are the body’s main source of energy and so should make up the majority of the meal. They can be found in whole grains, fruits, vegetables and beans and sports dietitians often recommend meals that are based around pasta, rice, bread or potatoes.  Whole grains take longer for the body to digest which means they provide slow-release energy, perfectly suited for longer periods of activity such as hiking or long-distance running. 


We couldn’t discuss the importance of good nutrition and hydration for exercise without mentioning protein. Found in poultry, red meat, fish, dairy, eggs and legumes, protein is essential for building and repairing muscles that are damaged during your workout. 

A note on planning meals

If you’re exercising at a moderate level then you shouldn’t need to make any special arrangements with regards to your meals. Eating a healthy diet and consuming the right amount of water should provide you with the fuel to be active. However, where you are planning to exercise intensely for an extended period of time, special provisions should be made. 

If you are partaking in prolonged or vigorous exercise you should eat a small meal that is low in fibre (and so easy to digest) between one and four hours before exercising. In terms of fluids, you’ll want to drink 400-600ml of fluid two hours before the activity and another 200-400ml fifteen minutes before. When exercising for several hours you may need to eat energy bars during the exercise period, and after exercising should be sure to top up on carbohydrates and fluids over the 24 hour period after exercise.