HEADACHES - Dehydration despite ample water intake!!!

I also wouldn't rule out exercise induced migraines.

I have to agree with the comments above. I live in Singapore, 28 degrees / 70%+ humidity on a "normal" ride. I use SIS for rehydration and energy drink. Typically I would drink .5 - .75 l/hr any more than that and you are asking for trouble even in such hot and humid conditions. I do not use caffeine at all, unless I'm seriously bonking and am close to home, and the it's good old "full fat Coke".

Tim Noakes is a good start, there is a really good "Marathon Talk" podcast (episode 39) with him in it which deals with the subjects raised above, find it in iTunes. Also try episode 41, with Dr Mike Stroud.

There is of course the alternative, which is reading Noakes' "Lore of running" which at 927 pages might be a little heavy for your needs, try the chapter on heat regulation though.

Good luck, and drink less!

@ Matthew - are you doing lectures at the road show soon?

@ wilf - hope you get this sorted. I had a terrible experience with dehydration and heat stroke a few years ago in Portugal.

Hi Wilf,

My name is Matthew Evans, I'm the Sport Nutrition and Science Advisor for Gatorade in the UK.

It is difficult to recommend a specific fluid and electrolyte replacement schedule as sweat rates and sweat composition is highly individual. It is advised to develop an individualised hydration strategy through routine monitoring of your body weight before and after training. The goal of drinking during exercise is to prevent excessive dehydration (generally accepted as 2-3% body weight loss).

Check out this video which outlines the steps to work out your individualised hydration strategy: http://www.gatorade.co.uk/video?v=SGNOvZMIgwY

Estimating electrolyte losses is much more difficult but signs that you are a ‘salty sweater’ are: a salty taste of sweat in their mouth; eye irritation when salt gets in the eyes; salt stains may be visible on clothing worn.

If you have any more questions, let me know.

It is unlikely, but it might be worth checking out whether you have Type 2 diabetes. High fluid intake plus headaches could be a symptom. Although as others have said, it is more likely to be you drinking when you don't need to.

Seems to be general consensus - drinking too much! I would have 3ltr over a similar distance but that's me. I generally use high5 zero's in my bottles and have the usual gels/bars/cake as well as some dosh to fuel up (obligatory cafe stop ) I only use a caffine gel for the final stretch home and have something to eat before I go out. Also, pace your intake of fluids. Also if you have a protein shake/choc milk shake once you get home you'll be refuelling liquids after exercise.

Is it only when exercising you shift a lot of fluids if you don't mind me asking?

Wilf - I think it was Cycling Weekly that had a feature on energy drinks a week or so back and they discussed the type of energy drink required/rates used.

Reckon its a combination over hydration and too much energy products.

Ive moved to drinking only Electrolyte stuff like Nuun tabs in a bottle. I might drink about 4ls over a 4.5hr period. Only 2 being caffiene enhanced electro, the others water.

Id also EAT at least 2 energy bars, iro 60gm of carbs over that period. If really working hard and warm weather, id add an energy gel or two but food gives your stomach something to work on rather than cramps because gel just releases energy alone.

Recent research CW mentioned was about the type of energy source. Basically, the old style drinks release too much of one single type and the stomach shuts down/doesnt absorb half of it.
The 2:1 type absorbs much better and in a more controlled way.

Do a bit of magazine research. We all have opinions and differing bodies. Overall, your headaches arent right so somethings gotta change. Id start with electrolytes in less water.

Bicarbonate of soda helps you retain water and is an legal ergogenic aid. You need to pre-load with 5 grams over a period of 24 hours.

Sorry - no links but do research it - my GB triathlete wife swares by it!

Yep, sounds like an absorption issue - you'd strugle to sweat out 5 litres on a 10 degree day. If the drink doesn't have the right balance of salts, your body won't be able to absorb it properly. Try sticking to electrolyte drinks as netclectic suggests and see how you get on.

5 litres seems a tad excessive, how did you manage to carry that much with you? If properly hydrated when you start I would expect to manage 75miles quite comfortably on 2 x 800ml bottles.

Which High5 power were you using? You might want to try more electrolyte rather than energy. I like the High5 Zero tablets.

That is way too much drink but i would also look at using an alternative to High 5 .I tend to find that High 5 are very high in caffeine and whilst on a ride you may go like a rocket the come down can lead to heaadaches when you have finished. SIS and ZipVit are two good alternatives or Bikefood do some good stuff too. Best of luck.

Hi Wilf

I have had the same experiences and suffice to say the problem is that you are actually drinking WAY too much! Have a google around for exercise-associated hyponeutraemia. Studies show that too many people competing in endurance events take onboard too much fluid, especially when it's hot. People die at marathons etc from drinking too much. No-one dies from drinking too little.

Also google Professor Tim Noakes for his views on the subject

Hope that helps

Hi Wilf

I have had the same experiences and suffice to say the problem is that you are actually drinking WAY too much! Have a google around for exercise-associated hyponeutraemia. Studies show that too many people competing in endurance events take onboard too much fluid, especially when it's hot. People die at marathons etc from drinking too much. No-one dies from drinking too little.

Have a look at the following link:
http://cjasn.asnjournals.org/content/2/1/151.long

Also google Professor Tim Noakes for his views on the subject

Hope that helps

Stu