Sports Drinks/What Fluid

The Northern Monkey

OK guys, i'm currently studying for a degree in Nutrition and Sports Science and figured that some of the stuff i've been learning might be put to some good use if i shared it....so here goes

OK there are 3 main types of drink that people associate with sport. They are:-
Hypotonic Drinks
Hypertonic drinks.
Isotonic Drinks.

There are some fundamental differences between all 3, and the only one that is actually classified as a "sports drinks" is the isotonic version.

Hypotonic Drinks :-
Contain approx. 2-4% carbohydrate, and are less concentrated than body fluids. This means that they are a low energy source but provide fluid at a greater rate that just water. They usually contain sodium with promotes water uptake in the body.
This type of drink is usually beneficial in hot climates or in low physical activities.
Examples: Volvic touch of water, Active O2

Hypertonic Drinks :-
Contain 8%+ carbohydrate and are more concentrated than body fluids. They are a high energy source but provide fluid at a lower rate than water.
These drinks are usually carbonated and contain caffeine, both of which are disadvantageous to athletes. Caffeine = dehydration, carbonation = gas/heavy stomach.
Examples: Kick, Red Bull

Isotonic Drinks :- The Sports Drink...(Before, During and After Sport!)
This type of drink contains 4-8% carbohydrate and also contains soduim and electrolytes and so can do 2 things at once.
It will replace fluid at a greater rate than water as it is at the same concentration as body fluid, and also has sodium to promote water uptake. The electrolytes that are lost in sweat are also replaced.
This drink also has enough carbohydrate in it to give an energy boost, and contains no caffeine and isn't carbonated.
Examples: Lucozade sport, Powerade RTD, High 5 Isotonic, Sis Go Electrolyte, Gatorade and Isostar.

Water????
Water is a good thirst quencher but not a good rehydrator.
Athletes that drink water, loose more through sweat and urine than they can drink.
It has no carbs for energy or electrolytes to stimulate fluid uptake.

How Much?
This is really down to the athlete themselves, but here is a little guide...

Before:- always start in a well hydrated state, having replaces any losses from the day before. A 500ml isotonic drink 2 hours before exercise is advised to promote hydration and to prime the stomace for water uptake.

During:- main aim is to make your intake = losses.
If the exercise is over 1hr it is recomended to have a carbohydrate containing drink of approx 200-300ml every 10-20 mins. As you can guess, the higher the intensity, the more fluid you will need and everybody is different.

After :- Try and replace fluid lossed by 150%. This is hard to calculate, but i would reccomend trying to drink 200-300ml isotonic drink every 20-30 mins untill your pee turns clear (a good indicator of being hydrated)!

One Final Thing
THIRST IS A POOR SIGN OF DEHYDRATION!!
If you feel thirsty you have already lost 2% of your body weight due to water loss!!

I hope this will help at least some people, as staying hydrated will help keep your performace top notch!!

Cheers,
Ben

Pippen33

Certainly acceptable as a 'sticky' thread.

The Northern Monkey

Cheers

Meat_Helmet

Great info fairly similar to what I've had to dig up on the internet the long way.

One comment regarding the urine colour being an indicator of hydration, from what I've read If you use a recovery drink which has a lot of Vitamin B I've noticed that it also turns your urine a bring yellow colour. This is also applicable to vitamin tablets.

3wheeler

I've been using the maximuscle viper drinks - there's no way for me to know how good it is, but you can mix it at different concentrations for before, during and post exercise. So, during mix 35g in 500ml (isotonic) and post mix 70g in 500 ml (hypertonic).

It tastes good, but most athletes tend to overlook it in preference of SiS, High 5 etc.

Regarding the comments on water, I'd always thought that water was better than soft drinks but not quite as good as isotonic drinks, and for most people was perfectly adequate. Do you have any info from studies on the benefit of istonic over water? How much better is it?

Is it dehydration itself that's the problem we're trying to avoid or the reduction in performance due to dehydration? Or looking at it another way, is the performance gain from the uptake of carbs during exercice that allows a higher intensity to be maintined for longer the aim?

Pippen33

although I agree with initial post, water (for myself) is best as I'll always have a salty snack out on the ride, and carbs, either simple or complex, and obtaining other minerals from diet. I'm using Garmin GPS 705 with HR to track performance and there's no difference in results with alternation of isotonic.

Never tried hypertonic on a ride, so maybe I should down 5 redbulls and call back.

dunker

cheaper alternatives?

homemade potions?

2 litres water + 1/4 tsp salt + few glugs of lime juice.
no cramping with this but i still need to eat if exercise is 2hours+

edit; what about the above with a crushed up multivit pill? that would be replacing electrolites to?

The Northern Monkey

3wheeler wrote:

I've been using the maximuscle viper drinks - there's no way for me to know how good it is, but you can mix it at different concentrations for before, during and post exercise. So, during mix 35g in 500ml (isotonic) and post mix 70g in 500 ml (hypertonic).

It tastes good, but most athletes tend to overlook it in preference of SiS, High 5 etc.

Regarding the comments on water, I'd always thought that water was better than soft drinks but not quite as good as isotonic drinks, and for most people was perfectly adequate. Do you have any info from studies on the benefit of istonic over water? How much better is it?

Is it dehydration itself that's the problem we're trying to avoid or the reduction in performance due to dehydration? Or looking at it another way, is the performance gain from the uptake of carbs during exercice that allows a higher intensity to be maintined for longer the aim?

Hey,
I'll try to dig out a sports journal for you about isotonic V water...either that or i'll try to upload some lecture notes for you (the notes arent that comprehensive tho). The main factor between water and isotonic drinks is the rate of water uptake in the body. Isotonic drinks will enhance water uptake due to its concentration and contents. Water on the other hand is a different concentration, so osmosis doesn't occur as easily.
The main reason water isn't used at an elite level is that athlets are unable to drink enough water to replace losses. Its hard to explain, but basically too much water will increase gastric emptying (peeing etc) = water loss. Isontonic drinks inhibit this due to sodium content and electrolytes.

Overall, dehydration is the overlying problem. If a athlete becomes dehydrated their performance will suffer. Energy metabolism (how the body produces energy) will suffer and also mental ability will be reduced. Also, blood flow is rduced meaning that muscles wont get enought O2 to produce energy, and any CO2/Lactic acid that has been built up cant be carried away from the muscles.

The idea behind carbohydrate in the drink is to give the athlete more fuel for energy and to balance the fluid concentration. Carbs are the main source of energy in events that last over 10 seconds, and when they run out fat is used instead (when fat is used it is called "hitting the wall" as not enough energy can be made via this pathway).

The Northern Monkey

dunker wrote:

cheaper alternatives?

homemade potions?

2 litres water + 1/4 tsp salt + few glugs of lime juice.
no cramping with this but i still need to eat if exercise is 2hours+

edit; what about the above with a crushed up multivit pill? that would be replacing electrolites to?

hey,
Yea homemade drinks are just as good as long as they are made up to the correct concentration. (unfortunatly don't have my own recipie but i'm sure there are many about on the net etc etc)
With regards of a vitamin pill and electrolytes, tha meain electrolytes are sodium,potassium,chloride and bicarbonate (so your pill would have to contain these)

Sodium regulates total water in the body
potassium is required for normal cell function ie heart beat regulation and muscle control
chloride helps with fluid balance
bicarbonate helps regulate blood pH.

The only problem you could come across would be excess intakes. which could have detrimental effects on preformance and bodily functions.

The Northern Monkey

Meat_Helmet wrote:

Great info fairly similar to what I've had to dig up on the internet the long way.

One comment regarding the urine colour being an indicator of hydration, from what I've read If you use a recovery drink which has a lot of Vitamin B I've noticed that it also turns your urine a bring yellow colour. This is also applicable to vitamin tablets.

Hey,
Cheers for pointing this out, as it is true that an excess of vitamin B will turn urine yellow. This is due to the kidneys removing the excess from body fluid and excreting it.

The Northern Monkey

Pippen33 wrote:

although I agree with initial post, water (for myself) is best as I'll always have a salty snack out on the ride, and carbs, either simple or complex, and obtaining other minerals from diet. I'm using Garmin GPS 705 with HR to track performance and there's no difference in results with alternation of isotonic.

Never tried hypertonic on a ride, so maybe I should down 5 redbulls and call back.

hey,
i think (or hope i have) said that everybody will be different.lol. The addition of carbs and sodium will definatly help and i guess its a defferent way of ensureing good fluid uptake.

as an example, the sports dietition that has take some lectures has to use many different sports drinks for the athletes they look after. ie some may like lucozade, but some prefere powerade etc, its all down to presonal preference! i' mean, i cant stand powerade!!!

As for redbull, its fizzy n theres lots of caffeine, you sure you wanna try it? (burps farts and dehydation dont sound too good to me )

Milkie

My 2p's worth...

How to make sports drinks...
http://news.bbc.co.uk/sportacademy/hi/sa/healthy_eating/newsid_2132000/2132209.stm

NikB

Surely if you pee clear fluid you are over hydrated and risking renal medullary washout which is not great for you. There should at least be some colour to the urine. Your own guidelines which suggest water in = water out would not make your urine that weak.

I'm also not convinced about the isotonic fluids rapidly rehydrating. Hypotonic fluids will achieve rehydration faster due to the concentration gradient. The lower solute content of the hypotonic fluids will allow the water content to be more rapidly absorbed to expand extracellular volume. However it is true that water isn't great on it's own but that's more because the solutes aren't being replaced than anything else. Dehydration is more complicated than simple water loss.

The Northern Monkey

NikB wrote:

Surely if you pee clear fluid you are over hydrated and risking renal medullary washout which is not great for you. There should at least be some colour to the urine. Your own guidelines which suggest water in = water out would not make your urine that weak.

I'm also not convinced about the isotonic fluids rapidly rehydrating. Hypotonic fluids will achieve rehydration faster due to the concentration gradient. The lower solute content of the hypotonic fluids will allow the water content to be more rapidly absorbed to expand extracellular volume. However it is true that water isn't great on it's own but that's more because the solutes aren't being replaced than anything else. Dehydration is more complicated than simple water loss.

ok, using pee color as a guideline is a primitive way of assessing an athletes hydration status, however i am uncertain as to wether many people have refractometers or urine analysis machines in their homes. This is supposed to be a simple guide to help aid people with their choices of sports drink when out cycling. Yes, very clear urine does indicate over-hydration....which is why it is used as a guideline to show that you should stop drinking....if you know of another simple way to assess wether you have replaced 150% of your water loss at the end of an event (the recommended amount), I'm sure that there would be quite a few dietitians out there in need of our help! oh and water loss = water loss DURING exercise, and total losses should be replaced by 150% AFTER exercise.

With regards to hypotonic drinks, i admit my wording was off and will rectify the script. However, isotonic drinks do promote fluid uptake more rapidly than water...ok maybe i used the wrong words, but isotonic drinks do contain more carbohydrate and electrolytes which is why it is the only type of drink to be considered a sports drink.

And of course dehydration is more than just bloody fluid loss you muppet. This was a guide to enhance peoples knowledge of different sports drinks which are recommended by sports dietitians and the reasons behind it. I also thought that a simple guide adapted and simplified from the American College of Sports Medicine about the intake of water during exercise would help people work out for themselves if they are taking on enough fluid during their exercise and how to help avoid dehydration!

NikB

No need to call me a muppet. At the end of the day you posted something you intended to be a guide which is in parts misleading. It's not hard to explain the losses involve more than water and that is why an isotonic drink containing the additional components is better than plain water.

The Northern Monkey

NikB wrote:

No need to call me a muppet. At the end of the day you posted something you intended to be a guide which is in parts misleading. It's not hard to explain the losses involve more than water and that is why an isotonic drink containing the additional components is better than plain water.

i have noted why the additional nutrients in the isotonic drinks are beneficial to athletes. i was merely trying to give some simple information about sports drinks and staying rehydrated! i'm not taking a biology lesson!

mudslinger

Thanks for sharing that information Ben.

I sometimes get migraines after exercising hard. I normally take just water with me on a ride but will now take an isotonic drink.

The Northern Monkey

Hope it helps
Migranes can be an indication of dehydration.

mudslinger

Yes I've just been reading up on dehydration. I did have a kidney stone last year as well which is another sign!

Any other nutrition tips for exercise are gratefully received

The Northern Monkey

mudslinger wrote:

Yes I've just been reading up on dehydration. I did have a kidney stone last year as well which is another sign!

Any other nutrition tips for exercise are gratefully received

No worries...what type of info you after

mudslinger

I guess something along the lines of:

Good things to eat pre, during & post ride. And the quantities per time of ride.

Thanks.

The Northern Monkey

OK, well as with drinks, everyone is different.

With high intensity activities, your carbohydrate stores are very important.

I'd try to load some carb on the evening meal before i was to ride, which would be somehing like a big pasta dish.
In the morning, a good breakfast is ideal, but nothing too heavy. So I go for cereal, and 2 slices of toast.
When it comes to the actual ride, I swear by the GO carbohydrate bars. I have 1 half an hour before I ride and depending on the length of the ride, i'll have maybe 2 more at rest stops during the ride.
You could substitute the GO bars with other foods such as flapjack, jellybabies etc, many people have different sugary foods that the swear by on a ride.

Post ride is quite important. You need to replace your carb stores as soon as possible. In the 1st 2 hours after exercise, carbohydrate metabolism is 2x faster that it would be after the 2 hours.

Here is a list of some carbohydrate containing foods.
The higher the GI (gycaemic index) the faster the carbohydrate contained in the food affects the blood glucose levels in your body ie it is absorbed quicker.

Hope that helps a bit... bit of a rushed reply so sorry if it doesn't make much sense!
B

supersonic

Vitamin supplements can have funny effects on pee colour! Especially vitamin C.

On some rides I do take just plain water, as the foods (ie bananas, fig rolls etc) contain minerals and salts.

If taking just a drink, a make up an isotonic solution.

The Northern Monkey

supersonic wrote:

Vitamin supplements can have funny effects on pee colour! Especially vitamin C.

On some rides I do take just plain water, as the foods (ie bananas, fig rolls etc) contain minerals and salts.

If taking just a drink, a make up an isotonic solution.

Yep, plus, because of the way the tablets are formed, you never uptake as much as the box says each tablet contains. If you eat your 5-a-day you shouldn't need supplements

supersonic

True! I sometimes take a bit more vitamin C if getting a cold, and does help me as I have chronic glandular fever. Turns your wee a very funny shade!

The Northern Monkey

supersonic wrote:

True! I sometimes take a bit more vitamin C if getting a cold, and does help me as I have chronic glandular fever. Turns your wee a very funny shade!

Aye, i've done research on vit C and how it helps reduce cold and flu. It has been proven in many nutrition journals that it can halve the length of a cold if a large amount is taken at the first signs of illness.
I slowly drink a litre of pure OJ as soon as I feel groggy, and I swear i've never felt i'll for longer than 2 days for about 5 years now!
just gotta be careful because a sudden increase of vit C can cause the squits :P

supersonic

Ha, that is true as well!

What about Zinc? I hear that is good too. The pills I get are 1000mg C, 15mg Zinc. Fizzy ones.

The Northern Monkey

supersonic wrote:

Ha, that is true as well!

What about Zinc? I hear that is good too. The pills I get are 1000mg C, 15mg Zinc. Fizzy ones.

Erm.. I did a module on Vitamins, Minerals and Micronutrients so I should know this

I'm pretty sure that there has been no significant relationship found between zinc and reducing the length of cold and flu. However, it does seem to be one of the supplements that people tend to take when they get ill.
Its normally children/teens and pregnant women that are recommended to take zinc supplements as its aids growth by catalysing enzymes. The enzyme activity does affect the immune system (but then again, most nutrients do) so good levels of zinc could help keep your immune function high.

supersonic

I need my immune system sorting, I am a wreck of illnesses lol.

Just started taking a taurine supplement, supposed to work well for people with M.E. as they have been found to have reduced levels.

The Northern Monkey

supersonic wrote:

I need my immune system sorting, I am a wreck of illnesses lol.

Just started taking a taurine supplement, supposed to work well for people with M.E. as they have been found to have reduced levels.

I've not actually covered ME but its related to viral infections isn't it? ie viral infections can bring on ME symptoms? (correct me if i'm wrong of course!)
So keeping your immune system topped up would be essential.
I assume your fairly active (you better be with that carbon zaskar :P), but exercise can actually have an adverse effect on your immune system.
When your exercising, more emphasis is put on supplying the body with energy for the muscles and actually producing energy, so you immunity is lowered. The low immunity will last until you've replaced the nutrients you've used.
Therefore, the 5-a-day (or more!!) is definitely essential to your diet.
There's a good guide about the 5 a day initiative HERE.

supersonic

Yes, my doc (or should I say Prof!) reckons I am getting M.E. from repeated glandular fever infections.

Not that active at all, I pace myself with activities and don't ride as much as I used to. Some days can be pretty bad. Gotta be careful not to overdo it or its 3 days in bed lol!