All Things To Help With Your Hydration

Why do I become dehydrated? Is this dangerous?

Through your daily activities, fluid is lost through sweating but also through the water vapour that is lost through your breathe. This will all lead to an increased state of dehydration which can then cause a general loss of performance and you will find that you fatigue far quicker.

Being dehydrated will lead to a reduction in blood volume, placing a greater strain on the heart, lungs and circulatory system. It has been reported that a 2% loss of body weight, through fluid loss, leads to a reduction in aerobic capacity by 10-20% during exercise lasting 90 minutes or more.

The more dehydrated you become the less able you are to sweat, this is due to the body prioritising blood flow to the muscles rather than the skin, therefore, the body is unable to manage body temperature as effectively.

How much fluid should I consume before exercise?

The main priority before exercise should be your hydration. As previously mentioned, if you are dehydrated and are looking to perform at the highest level that you possibly can, then you are physically unable to do this. A study involving long distance runners reported a 2% drop in body weight through fluid loss, caused a substantial drop (6-7%) in the speeds they were capable of reaching.

In an ideal world prevention of dehydration is better than curing it. This should be thought about more so when exercising in hot and humid conditions, as you will dehydrate quicker. To monitor your hydration status you should observe the volume and colour of your urine. There are many charts available to compare the fluid colour with, whilst your urine should ideally be pale yellow in colour and not completely clear.

It is recommended that an athlete should consume 5-7ml of fluid per kg of body weight slowly over a 4-hour period. Therefore if the athlete weighs 70kg they should consume 350-490ml of fluid pre-exercise. Always carry a water bottle with you, this allows you to manage your own hydration rather than depending on a coach.

What should I be consuming during exercise?

Fluid consumption throughout the period of exercise will vary from athlete to athlete. The American College of Sports Medicine reports that there are no specific recommendations on fluid intake during exercise due to the differing sweat rates and composition of the sweat. The aim of maintaining hydration throughout exercise is to limit the total loss of performance.

Exercise will vary in difficulty, this depend on the environment or intensity of a session. Therefore, the best strategy is to observe the fluid loss that takes place through sweating before and after a standard session. This is done by taking the weight of the athlete before and after exercise; with the aim to limit the dehydration in future sessions to less than 2% of body weight. Alterations then can be made on how much should be consumed dependent on the environment.

How will fluid help my recovery?

Following exercise the body needs to have the fluid balance returned to normal; this involves the restoration of water and electrolytes that were lost through sweating. Researchers have recommended that you should look to consume 1.2-1.5 times the weight lost following exercise. Working on the assumption that 1kg of body weight is the equivalent to 1L of sweat, you should look to replace the fluid loss with 1.2-1.5L of fluid. This should not be drunk in one go, however, drunk steadily over a longer period of time.

A key reason to maintain good hydration following exercise is for the recovery of the athletes muscles. This is a process known as protein synthesis; it plays a role in the rebuilding of muscle, and requires the muscles to be hydrated to work. Therefore, poor hydration will lengthen the time at which the muscle recovers following exercise.

Water versus Sports Drinks?

When performing moderate-high intensity exercise you may feel nauseous when consuming water, this can be due to dehydration or the intensity which you work at. A sports drink will aid you during exercise at the high intensity when it is performed for longer than an hour. A sports drink containing 40-80g of carbohydrate per litre can promote hydration and normalise blood sugar level. If the exercise is longer than 2 hours in length or you are sweating heavily you should opt for a sports drink that contains sodium.

There are three main types of drinks available to us in daily life; hypotonic, isotonic and hypertonic.

  • Hypotonic drink – This drink contains less than 4g of carbohydrate per 100ml. This has a low osmolality (concentration of particles in comparison to that of the body); due to it being more dilute than the body this is absorbed faster than plain water.
  • Isotonic drink – This is the typical sports drink and has a similar osmolality to the body. This drink offers the ideal compromise between rehydrating and refuelling. This is absorbed as fast or faster than water.
  • Hypertonic drink – This can be categorised as a ready to drink soft drink, this has a higher osmolality than the body with a higher concentration of electrolytes, this is absorbed more slowly than water.

How to make your own Sports Drink from home?

What are the sports drinks available to me?

There are two designated types of sports drinks that are available to us. You have the choice of either a fluid replacement drink or a carbohydrate drink.

  • Fluid replacement drink – This has dilute concentrations of electrolytes and sugars (carbohydrates). Sugars that you will often see in these drinks are glucose, fructose and sucrose. The aim of this type of drink is to replace fluid faster than plain water, whilst the added sugar in the drink will maintain blood sugar level.
  • Carbohydrate drink – These will provide a greater amount of carbohydrate per 100ml than fluid replacement drinks. This is typically made up of maltodextrins. You would typically use this drink following exercise by way of recovery rather than rehydration.

Both of these types of drinks can be either hypotonic or isotonic.