Electrolytes and carb drinks - best hydration?


did a longish (20+ miles) run in the sun recently and thought I'd drunk enough (PSP 22) - but ended up quite light headed and suffered a little bit.

Got me thinking re advice re whats the best fuel for ultras - especially in the hot weather. Next race is July.

Should I try the zero cal electrolyte drinks tabs - are they better at rehydration. Can't get my head round zero cals when I need calories and more calories on the run? Should I split my refuelling from my hydration and is combining them actually detrimental?

Are there formulations/drinks that are better for ultras - carbs, calories and electrolytes - especially for higher sweat loss.

Is the light headedness purely hydration or is it minerals potentially? I've suffered a couple of times in hot runs and sure I'd taken in enough liquid.

Any advice, thoughts?


  • How much did you drink ? How hot was it ?

    I often run 20 miles with no liquids, but I'd need water in the summer.

    Was it just the sun that did it and not the hydration issue do you think ?
  • David J 27David J 27 ✭✭✭

    Hia. Thanks. Drank  about 1.2  litres spread out. It was warm and sunny not very hot. Altho thats enuff for me to create a fair bit of sweat. Dripping of my peaked cap like a rain shower. 

    Never thought of that - but could be impact of the sun/heat on someone who's body was meant for more winter like climes......rather than hydration.

    As a connected question was wondering what the benefits are of zero cal hydration drinks over carb/energy drinks..,. if any .. to maximise hydration benefit....

  • I put some Maltodextrin in my water, depending on how hard the training session will be and what comes up on the next days. In warmer conditions I always put some salt in.

  • HA77HA77 ✭✭✭

    If you're drinking a fair bit, it may be hyponatremia (low sodium). If that's the case, drinking more will make it worse by diluting the blood further and carbs won't make a difference. Drinking electrolyte drink may help but generally it has a lower sodium concentration than your blood, so drinking lots will also dilute it. I think the general advice now is to drink only to your thirst, rather than a preprescribed amount (applicable for water and electrolyte drink). 

    I like to do my long runs without carbs on the, perhaps misguided, notion that it will train my body to burn fat faster, so if I were you I'd be using the no carb electrolyte stuff and only drinking to thirst. I generally only take water on long runs and might have 250-500mL over 20 miles depending on how hot it is.

    Here's some more reading if you're interested:



  • David J 27David J 27 ✭✭✭

    Thanks HA77. Really interesting and useful advice! There's a logic to that - hot day - dehydrate/thirst - drink more - blood dilutes and less salt - so headache and drop off of performance.

    Double checked my energy drink and has zero salt. I switched from Zipvit ZV1 (which has salt and minerals) to PSP22 (Go) which has zero salt. In blind assumption on just a change in brand and taste. I need to read the labels. 

  • Lee RoiLee Roi ✭✭

    Hi David,

    I found this page about Electrolyte Balance very useful when I was researching electrolytes and water intakes for an Ultra. It explains the effects of having too high/low an electrolyte intake against too high/low water intake. It's interesting and knowing the effects that each condition has is very helpful to recognising where you are on the handy table it shows.
    Although you'd rather not be in some of the positions in the table, its good to be able to recognise the effects.

    It's on the 'S-Caps' website, but it doesn't really focus on products, more the facts.

    Hope its useful for you.

Sign In or Register to comment.