by Mark Wolff

Hydration is such a spoken about topic not just in sport but every day life. I mean water makes up around 60% of the human body depending on age and sex which means its extremely significant.
Hydration is also one of those things that most people get wrong. Over the years I have witnessed so many hydration disasters and mainly due to a lack of knowledge or understanding as to how the human body works. For years the fear of dehydration did its rounds in sport and a general trend of preempting thirst began to move in the close knit circles of the endurance world. Then that came along with over consumption of fluid leading to hyponatremia cases and in some instances death. Enter the debate on cramping and hydration and salt entered the scene and a new trend started with a focus on cramp mitigation. Again the messages were a miss with tons of salt tablets being swallowed during events with little understanding as to how and why.

Let’s clear the smokescreens a little and keep it very simple so that when you are resting, training  or racing you get your hydration correct.

During the day I often suggest that an individual who is resting from exercise should take in around 20-30ml’s of fluid per a kilogram of body weight and over a period of time to maximize the fluid absorption. As an example a 70kg individual will benefit from drinking around 1.4 – 2.1 liters of water in a day.
Exercise brings along a new range of dynamics because the body’s natural cooling system is of course sweat. During exercise a varying amount of fluids and minerals are lost due to sweat and the volume lost is dependent on a number of conditions:

1.       Temperature
2.       Humidity
3.       Individual

The hotter the climate the more sweat will be excreted to cool the body down and in humid conditions this increases even more. Each individual will have different rates of fluid and mineral loss and this can be genetic as well as how acclimatized the person is to that particular climate. As a simple example if someone has been exercising in cold winter months and suddenly goes to a hotter climate their body will not be acclimatized to those conditions and cooling will not be as efficient as opposed to an individual who has been consistently training in a hot climate and is used to those hotter conditions.

The idea of simple hydration is to basically replenish the amount of fluid lost in the form of sweat by drinking it back. It sounds simple but it isn’t really as this does not mean if you lose 1 liter of fluid in the form of sweat in 60 minutes that you can drink 1 liter of water in 60 minutes to gain it back. You see the body needs to absorb the fluid and the amount of fluid you are capable of absorbing is unique to the individual as well as influenced by factors such as the composition of the fluid being plain water or a solution of carbohydrates and or minerals. Each drink has a different rate of absorption and this is dependent on something called tonicity. Tonicity is easily explained as the effective osmotic pressure or concentration between  two solutions. In hydration terms this is simply the concentration of the fluid ingested versus human blood.

There are basically three classifications isotonic, hypotonic and hypertonic.

Isotonic which is quite commonly known is where the ingested solution has a similar concentration to that of the blood in the form of sugars and salts. Isotonic drinks are used to provide a balance of energy and hydration. The solution is absorbed fairly well along with the energy portion of the carbohydrates being supplied. An isotonic drink consists of a 6-8% carbohydrate portion in the solution and around 45-70mg of sodium.

Hypertonic sports drinks contain a higher concentration of carbohydrates to sodium and basically is used mainly for energy provision as opposed to maximizing hydration because the fluid isn’t readily absorbed such as in the case of isotonic drinks. A hypertonic drink is mainly used for providing fuel to the body but certainly not for hydration purposes. This is where many athletes make a mistake not understanding the rate of absorption and often causing GI (gastrointestinal) distress due to over consumption. A simple example is consuming a gel without the correct amount of fluid to allow for the proper dilution ratio.

Hypotonic drinks have a low carbohydrate composition with a higher sodium composition which means energy derived from the drink is low but fluid absorption is much higher. Where I find hyptonic drinks useful is certainly for people who want to keep hydrated and burn more body fat or manage weight issues. It’s no secret I am a fan of intermittent or fasted training and in my mind a hypotonic drink becomes your best friend.

It might sound complicated but its not really. The point I want to stress is firstly one needs to separate out energy and hydration requirements. There is no point in combining them as your actual requirements on either end will get confused and energy should be a separate measure to hydration in order to make sure you get your volume intake correct. This is where the blog becomes a little more interesting.

I have spoken previously about the duration and intensity of training but now add in temperature conditions which should roughly determine sweat rate.

The rule of thumb is basically the hotter the conditions and the longer you are going for and the higher the intensity the higher the need for fluid replacement to keep the engine cool. The issue though is most athletes over hydrate to try to cool the engine and when this happens the body isn’t capable of absorbing that amount of fluid and this just leads to major issues. Possible reasons for this is either the athlete hasn’t selected the appropriate solution for hydration and the fluid just builds up without being absorbed or that the athlete just over consumes fluid. An over hydrated athlete is at more risk than a slightly dehydrated athlete.

How do you deal with this? Simple, two possible ways. The one is to spread your fluid intake out and only drink to thirst. If you have over-hydrated you will know by the fact that your stomach is bloated and you can feel and even sometimes hear the sloshing in the stomach. This is called the washing machine effect. In this situation one needs to stop drinking and wait for the absorption to happen or ingest some salt and or sugar to help pull the fluid out quicker. The other way to increase fluid absorption is to of course make sure you have a hyptonic drink which has a higher concentration of salt to carbohydrates to maximize fluid absorption. A hypertonic drink should never be relied on for hydration that is not its purpose at all as mentioned above its for energy provision and trying to do so will cause stomach issues for sure.

I personally use 32Gi Hydrate which is purely hypotonic and contains zero calories mainly for hydration purposes and due to doing mostly fasted training it allows me to ensure the hydration portion is spot on. When it comes to energy and I decide to ingest carbohydrates I either make a separate hypertonic drink which has a higher concentration of measurable carbs in a fluid form or I take from external food sources in the form of food bars or chews.

Let’s touch on the topic of hydration and cramping. To be completely honest there is very little evidence that suggests that dehydration is a major cause of cramping. For many years athletes have taken salt tablets to try to prevent it by increasing fluid absorption but science has shown that the main trigger of muscle cramping is mainly muscle fatigue, and 99% of the time this is mainly due to under trained muscles. As an example an athlete goes out at a harder pace than he has trained at or he stresses the muscles for longer periods of time than his body is conditioned to.

I work frequently at running, cycling and triathlon race exhibitions and one of the most common question’s I get asked is “do you have something to stop cramps”. My answer is usually “how well have you trained?” When the guy tells me he hasn’t done much I know for sure no matter what he takes the inevitable cramp can set in. I have athletes swearing blind that alkaline tablets, salt tablets, magnesium tablets and all the wonderful supplements prevent cramping. However it is not so simple there is just no major evidence to support that. If cramping were mineral deficiency related then why is it that only the quad cramps or the calve or only one side of the body? Generally cramping that is nutrient deficient related would be experienced across the entire system if it were the case.

Some of the top researchers in the world have shown that when a cramp sets in walking and stretching will remove the cramp. If this was a mineral deficiency it wouldn’t release that quickly. There are certain individuals who do have a susceptibility to cramping and if it is related to mineral deficiency its quite easy to pick up and to try to correct. Of course consuming the correct minerals during a training session or a race is needed for bodily function and performance.

An athlete that dehydrates can still perform at a very high level. You will find most elite athletes at the end of a marathon or ultra distance event are dehydrated, and its quite normal. However over consumption of liquid will see your demise and very quickly. It’s easy to resolve a dehydrated state by taking in fluid, but to get rid of fluid when you over drink in an event is not simple and you wouldn’t want to be in that situation. So make sure you do understand which type of drink you are consuming, its purpose whether energy, hydration or a combination of the two and test it in training to ensure you understand how it impacts the body. Over and above that you need to train in similar conditions to those you will race in otherwise you will not get a true test of how the body will respond to that method of hydration and energy intake. Always be prepared, understand what you are consuming and exactly how the body responds to it as if not you are just taking a chance and could be putting yourself into  a precarious situation.

If you are wanting an awesome hyptonic drink then look no further than 32Gi HYDRATE effervescent tablets, also loaded with Vit B and Magnesium to keep the energy system sharp.

Stay healthy,

all the best


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