Hydration advice

Gasperoni

I've been riding for about 6 months now, getting on for 1k miles. 46, overweight (15st10, 5'11) and just riding for fitness, trying to increase my endurance rather than speed. Learning a lot as I go along, but generally just trying to go with what feels right. I tried taking on water at regular intervals, but wasn't sure whether it was too much or too little, so asked a friend who cycles a bit who responded with the eminently sensible 'drink when you feel thirsty'. My problem is that I did a 75 mile ride and got through a whole 400ml of water. In fact, I suspect even some of the times when I drank was because I felt I should, not because I felt thirsty. It didn't feel like a problem, but my question is
a) is it? and
b) if it is, what are the consequences?

Philby

Are you sure you got your amounts right?

Most bottles have a capacity somewhere in the region of 500ml to 800ml. If you only drank 400ml over 75 miles that isn't even one bottle - far too little for such a long ride IMO. Your fluid intake will vary with the weather (I drink a lot less when its cold), speed / effort you put in, and the topography of your route.

As its obligatory to stop for tea or coffee and cake on a ride you would obviously have taken extra liquid in :roll:

Pituophis

On a ride of that length I would expect to drink at least 2 full 750 ml bottles, and in warm weather probably stop to fill one up again. But everyone is different so you will get lots of contradicting answers.
400 ml doesn't sound anywhere near enough though! :shock:

fudgey

I drink a lot, upto 750ml per 15 miles in warmer weather, whereas my mate who i ride with hardly drinks at all.

last weekend we done 52 miles, i drank my 2x 750ml bottles and half of one of his...

he on the other hand had drank id guess 2/3 of a bottle.

but then on sunday we done 28 miles (had to cut short as i got a pain in my knee...) anyway, my mate came to pick me up and noticed he had forgot his bottles, i put 4x bottles in my bag, with clothes, wallet and house keys..

then when we got to our destination realised i had left the bag in the garage..

luckily the other mate who we met had 2x 500ml bottles so i had one of those, and they shared the other.
i think i drank just over half of it by the time we got back as i was well aware to ration the water.

so there we go, no real answer!

slowbike

Well done on 75 miles ...

You should drink before you feel thirsty - plain water is ok, but if you're sweating a lot then you also need to replace the salts you're losing - various ways you can do this, my chosen method is a zero calorie drinks tablet.

I will easily get through a 750ml bottle in this weather on an easy club run of around 50 miles. A few years ago that would've been 2 x 750ml bottles because I would've been working harder for the same speed & distance.

mpatts

I drink little and often rather than when thirsty - depends on how hard the ride is but I usually do 750ml per 25 miles.

CiB

Gasperoni wrote:

My problem is that I did a 75 mile ride and got through a whole 400ml of water. In fact, I suspect even some of the times when I drank was because I felt I should, not because I felt thirsty. It didn't feel like a problem, but my question is
a) is it? and
b) if it is, what are the consequences?

?
400ml = 0.71 pint

You're not seriously questioning whether drinking a whole ¾ of a pint is bad? I'd suggest you keep away from pubs...

rs6mra1

Isn't there a rough guide to determine how much you need to drink by weighing yourself naked before an ride and then ride for an hour and then weigh yourself immediately after. I can't recall how you determine how much fluids you need from there......................And obviously it would different in the summer months. Maybe someone else can fill us in on how to determine how much fluid is require within an hour

ai_1

If you're considerably lighter after a ride than before, the difference is the amount you have dehydrated. (Unless you took a toilet stop.) If you're coming back significantly lighter than you start then you're probably not drinking enough. Colour of urine is also an indicator. Darker = dehydrated.

As a rough guide I expect to drink approx 500ml per hour of medium effort. Predictably, I find I generally use less in cold weather and more when it's warm.

On longer rides such as sportives when I've waited until I was thirsty to drink I've found I was playing catch-up for the rest of the ride and didn't feel great by the end. Pretty sure this is down to insufficient liquid intake. Now I make a concious effort to have a sip every couple of kilometers regardless.

Gasperoni

Many thanks for the replies, all very helpful.

I imagine pace/exertion comes into the equation too to some extent and I wasn't pushing on, but I would still expect some degree of dehydration to be a natural consequence. I will have a cup of tea when I get back and rehydrate naturally over the next day or so, but what I'm not sure of is whether there are any less obvious consequences of the dehydration that I need to be aware of? I'm no athlete, so feel a bit daft talking about things like recovery and muscle development, but maybe I'm scoring an own goal with my current approach? I prefer the 'drink when you feel thirsty' approach with a cup of tea when I get back, but if I'm effectively taking two steps forward and one back then it would make sense to be more methodical about it.

surrey_commuter

everybody is different but you are doing the exact opposite of what conventional wisdom suggests. This does not mean that you are wrong but why not try drinking a lot more... ie at least 500mls before you leave and then try and drink 1 litre whilst riding and then another litre when you get home. See if you feel any better for it

Gasperoni

I don't think I helped myself with the subject I gave this post. It probably needed to be more specific, like 'Hydration advice'

Anyway, I've been reading through a lot of information on the t'interweb to try and get some answers, There might be some cycling specific considerations I'm not aware of, but here is what I found, in case its of any use to anyone else.

1. The primary effect of dehydration is that it interferes with the ability of the body to cool itself through sweating
2. The results of that depend on the degree of dehydration, as well as other factors, including temperature and humidity. Results range from reduced efficiency to death. Not being able to cool yourself and having the environment able to raise your core temperature to dangerous levels is why severe dehydration is more dangerous when it is hot.
3. The degree of dehydration can be calculated by comparing your weight before and after the exercise. Very broadly, a loss of 1-2% isn't ideal but not really anything to worry about. 3-4% and you start to see some significant declines in performance in the region of 30%. The sliding scale continues, but anything over 4% starts to get more concerning.
4. As the body can't process liquid as fast as it loses it, hydration is more a matter of putting off the point at which your performance degrades due to it.
5. It is possible to over-hydrate, which can be just as dangerous.
6. It has been reported that the ability to recognise dehydration, or simply when you need to take a drink, diminishes when you reach 45-50. If that's true, it rather messes up my preferred 'drink when you are thirsty' approach.

Time to move away from 'what does not kill me makes me stronger' and for me to pay a bit more attention to hydration. On the other hand, I also now know that my particular 75 mile trip wasn't a risk as I think I lost 2-2.5% on the day. I suspect on a a warmer day I would have taken more water on.

(and it looks like I can change the slightly misleading Subject line. hopefully doesn't cause too much confusion)

kajjal

Just listen to your body, we are all different. Road riding I don't use more than two 750ml bottles over four hours in the summer. Four hours xc mountain biking in 30c heat I can use three bottles. It just depends on what you are doing and on how your body reacts. If you get very dehydrated you will really know about it. I drink about a pint of water before I start in the summer which helps.

Sutton_Rider

Interesting - I did a 50 miler the other week and only took a couple of sips. Last week I did 40 miles and didn't drink at all. No wonder I ran out of steam at 30 miles :oops:

Schoie81

I watched a tv programme about this very subject last year. They said that every year during the London marathon the first aiders treat more runners suffering the effects of having drunk too much water, than those having not drunk enough. Looks at the pros - they take a water bottle, drink a mouthful, poor some over their head if its a hot day, then throw the rest away. A lot of amateurs see a water station and think that means they should drink, so they take a bottle and drink it, then take another at the next and so on. They concluded that when you feel thirsty, that's your body telling you you need a drink - its not rocket science (although I cannot comment on your findings that this natural 'signal' diminishes as you get older...)

I sweat a lot, but on a nice day (not too hot) I take a full bottle of water with me, and on a 30(ish)mile ride, 9 times out of 10 I'll get home having not drunk a drop. Over 30miles, or if its really hot, I'll usually drink during the ride but otherwise, for me, I don't feel its necessary and haven't felt any ill-effects from this approach. I do tend to drink a little more water before my ride, but not a lot, and it'll be over a few hours, rather than downing a pint of water before I jump on the bike....

cougie

On a ride in weather like we have now I'd probably get through one bottle or so - so 700ml in 50 or 60 miles.

If its colder - then I sometimes don't drink at all.

If its hot - then I'd go through 2 bottles and have a refill.


I dont think you need analyse it too closely though. You're a big guy and theres a lot of fluid in you anyway. take a bottle and drink if you want to. If you get headaches or peeing very yellow wee - then you need to take on a bit more.

Dont forget that you can add electrolytes or sugars to the water to help fuel you or keep the minerals up in hot times.

simon_e

Sutton Rider wrote:

Interesting - I did a 50 miler the other week and only took a couple of sips. Last week I did 40 miles and didn't drink at all. No wonder I ran out of steam at 30 miles :oops:

It may not be a shortage of water that caused that (unless you were already dehydrated before you started).

Schoie81 makes an interesting point. It seems lots of elite marathon runners drink very little during a race. This has been a hot topic for a while, as some question the advice to drink lots while exercising (a lot of it repeated by sports nutrition companies). Alex Hutchinson has discussed this in a number of articles including these:
http://sweatscience.com/drinking-during ... u-thought/
http://www.runnersworld.com/drinks-hydr ... nuing-saga

+1 to cougie's comments. Fluid loss on a steady ride in cool weather may be less of an issue than you think. If you felt fine and your pee wasn't too dark afterwards then you're probably not doing much wrong. Experiment and see what works for you.

ai_1

Simon E wrote:

Sutton Rider wrote:

Interesting - I did a 50 miler the other week and only took a couple of sips. Last week I did 40 miles and didn't drink at all. No wonder I ran out of steam at 30 miles :oops:

It may not be a shortage of water that caused that (unless you were already dehydrated before you started).

Schoie81 makes an interesting point. It seems lots of elite marathon runners drink very little during a race. This has been a hot topic for a while, as some question the advice to drink lots while exercising (a lot of it repeated by sports nutrition companies). Alex Hutchinson has discussed this in a number of articles including these:
http://sweatscience.com/drinking-during ... u-thought/
http://www.runnersworld.com/drinks-hydr ... nuing-saga

+1 to cougie's comments. Fluid loss on a steady ride in cool weather may be less of an issue than you think. If you felt fine and your pee wasn't too dark afterwards then you're probably not doing much wrong. Experiment and see what works for you.

Of course elite marathon runners are only running for a bit over 2 hours. The slower runners will likely need more. Still I'm not surprised some overdo it. I currently run up to half-marathon distance and never carry water when I run. I'll have a sip during an event if it's provided on course but that's about it. However I see lots of runners, they all appear to be novices, carrying water bottles as they run. How can you run properly with a water bottle sloshing around in one hand? I'd be very surprised if most of them are out for more than 5km to 7km runs so what on earth do they need water for?
However, on the bike when I get out for a long cycle such as a 160km sportive I do find I need to drink a little regularly or dehydration does become a problem. Based on experience, waiting until I'm thirsty doesn't seem sufficient.
I think I typically drink about 400-500ml an hour in warm weather. Less when it's cold.

cougie

When i started running I'd take water out with me too. I think its like a security blanket. Now I'll happily run 20 miles in cool weather with no liquids. Hot weather is different though.

Trisross

If your thirsty or hungry on a ride its already going wrong. Drink and eat at regular intervals, the idea is to eat when your not hungry so you don't blow up, same with liquid. I asked the same question before I did my first 100 and the bike shop owner said have a nibble every 15 mins. One bottle an hour is a good rule of thumb.

Make sure its something you like or you wont eat/drink it and its pretty important when you get to bigger miles like 75. Well done by the way that's a good ride.