Electrolytes and Their Importance to Endurance Athletes

E is for Electrolytes

I have recently finished the book The Runner’s Diet and it was chock full of information regarding carbohydrates, proteins and fats.  Or to use one term:  macro-nutrients.  There were chapters dedicated to these macro-nutrients and rightfully so as most people seem intent on focusing on these three, but as an endurance athlete there is more to being prepared than consuming a balanced diet of 55%-60% carbs, 15% protein and 20%-25% fat.

There are electrolytes to worry about.  What is an electrolyte?  Electrolytes are the bodies salt which will help maintain fluid balance in your organ systems.  They are important in maintaining the integrity and function of your body.  Your next question is what are the normal names by which I might know what an electrolyte is?  The answer to that question is sodium, potassium and magnesium.

There have been discussions, that I found online, about the need for electrolytes  and there are many interesting questions and points. Too much or too little? What is right for you? Are there dangers to watch out for? These are all valid; but the answers varied.  Endurance sports results in a lot of sweating which obviously results in a salt loss as well as water loss.  Your body does have an automatic process by which it balances salt and water concentrations.  Similar to water consumption guidelines, there is no hard and fast rule for replacing electrolytes.  Replacing electrolytes will vary depending on the climate you are in (hot temperatures are different than cold temperatures for water loss) as well as the intensity of the activity.

From what I gathered there is no need to replace electrolytes immediately if the exercise lasts less than 3-4 hours.  Since most of us will be on the course for a half-iron distance, and certainly Iron distance race longer than 4 hours electrolyte replacement becomes an issue.  So how do you replace or avoid having to replace a lot of your electrolytes?  I read this on ultracycling.com and it made a lot of sense to me:


A plan to avoid the problems
First of all, you can reduce your tendency to lose sodium by what you do when not training or competing. You can reduce the amount of sodium in your daily food. That will increase the level of aldosterone so that your body retains sodium better. Choose less salty foods. Use Morton Lite Salt in your salt shaker. That will reduce sodium and increase your potassium intake ( as will eating fruits and vegetables ).

If you expect to compete in the heat, get heat acclimated as soon as possible. That will reduce your sweat rate under hot conditions.

While you train, stay cool so that your sweat rate is lower. Wear light clothes, keep your jersey wet, and/or put ice on your neck.
To satisfy your needs in a hot event you can take sodium in different forms. The simplest is table salt (a pinch per hour ). If an aid station has salt and boiled potatoes, you can dip a potato into the salt before eating it. V-8 and tomato juice are also good sources.Consume supplemental salt or electrolytes during the event. Most sports drinks have sodium levels that are fine for shorter distances, but inadequate for longer distances. Most gel products have insignificant amounts of sodium.

You can use an electrolyte replacement supplement, but check the sodium content. Some riders take salt tablet such as Thermotabs. Some athletes use Stamina Electrolyte Tablets but those are not a good source of sodium or potassium (they are a good source of calcium and magnesium ). Some athletes use SUCCEED! Buffer/Electrolyte Caps that are formulated specifically for ultradistance athletes such as cyclists, triathletes and runners to supply sodium, buffers and sufficient amounts of potassium.

As always, you need to drink. Don’t wait until you are thirsty; the human thirst mechanism is too slow and inaccurate. As the adage goes: Eat before hunger, drink before thirst.

When you finish a long training ride or event, you will usually have a deficit of water, calories and sodium. You will have a much smoother recovery if you replace all of those promptly. Soon after finishing, you can take an electrolyte supplement, 200 calories of carbohydrates and drink water until you are no longer thirsty, and are urinating again. In the days that follow, you will probably find that you have more energy and fewer aches and pains if you have promptly replaced water, carbohydrates and sodium after your long ride.

Water or Gatorade?

And while it made sense to me I don’t enjoy Gatorade because of its taste.  There are other reasons as well but in the end taste trumps all and I don’t like how it tastes.  I use Accelerade from Pacific Health Labs on the bike.  It has the proven ration of 4:1 Carbohydrates to Protein and it also contains 180mg (8% of your daily value) and 55mg of Potassium (2% of your daily need.)  It contains only 60 calories per scoop in 12 fluid ounces.  Very good numbers especially when you compare it to Gatorade, which has 275mg of sodium in 150 calories for a 20-ounce bottle.

You could eat a mini dill pickle and get 290mg of sodium with only 5 calories, but try eating that on the bike after you’ve been riding for 2+ hours.  Want some celery on the bike?  Well, it does have 100mg of sodium in only 20 calories but again the thought of pulling that out of your bento box just doesn’t add up.

I will gladly consume the Accelerade and the PowerBar Harvest bars that I have been training with.  I am consuming 1 PowerBar harvest bar every hour by cutting it into 4 pieces and eating every 15 minutes.  They have approximately 220 calories per bar so that meets my needs, and include 150mg of sodium and 240mg of potassium.  During my training I have not had any hunger pains running off the bike so I know that this works for me and I will not be changing it this close to race day.


What do you drink or eat to replenish your electrolytes?  Did you know a banana has 422mg of potassium, but only 1mg of sodium?

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  1. Nora says:

    I’ve been trying to eat more bananas and you know I’m still working on my electrolytes. Some day I’m barely drinking 20 ounces. Yesterday I did manage 60!
    Nora recently posted..Commence Smell Like Pool RoutineMy Profile

    • Jason says:

      The easy way to drink water is to take double sips each time you sip. You get 2x the intake without any additional effort and you will be hitting your ounces.

  2. Jon says:

    Bananas are the $hit!!! Not sure I could do this stuff if Bananas never existed….been finding I have been eating 3 a day. Oops! (not really :) )
    Jon recently posted..The Nerd Report- Week in ReviewAND ANGRY BIRDS RIO!!! WOO HOO!My Profile

  3. Marlene says:

    I tended to believe that more salt is always better for endurance athletes, but what you are saying about reducing (when not training) makes a lot of sense – thanks for another informative post!!
    Marlene recently posted..Too good to be trueMy Profile

    • Jason says:

      Crazy the stuff we learn isn’t it. I never even thought about sodium. Just ran and cycled and swam. Didn’t think anything of salt, and now I know.

  4. jennifer says:

    Really glad you posted this… had no idea that day-to-day high salt intake would cause you to lose sodium more easily. I am a salt-o-holic! Looks like I should start dialing it down a bit.
    jennifer recently posted..Crissy Field runMy Profile

    • Jason says:

      If you use items like soy sauce and tamari in your cooking you will get your sodium without having to add more. One of the things to look at as you are cooking is that sodium intake and the numbers will probably cause you to not reach for the salt shaker.

  5. MissZippy says:

    Hmm, celery. I suppose not the most convenient item to stash while training/racing. All great info, Jason. Thanks for sharing!
    MissZippy recently posted..Ive crossed some lineMy Profile

  6. natasha says:

    If I drink Gatorade I have to water it way down if not it makes me sick to my stomach. I have 1 banana a day mainly because I have this idea it helps with muscle cramps and I get crazy muscle spasms in my calf and feet. I usually drink straight water unless it’s a half marathon or longer.
    natasha recently posted..Spring is in the air!My Profile

    • Jason says:

      Natasha – found this online and might help you out as a cause for muscle cramps, thus bananas will help you.

      Low potassium: Low potassium levels occasionally cause muscle cramps, although it is more common for low potassium to be associated with muscle weakness.

  7. Rachel says:

    Ooh. Where did you find the 3 to 4 hour rule for electrolytes? I strongly disagree with that time frame. You’re right that many factors goes into replacement of electrolytes and electrolyte drinks and replacement are NOT needed for exercise that is under 1.5 hours. Yes, some people may be fine after 3 or 4 hours – but if it’s warm out, if the person is a salty sweater, if they have a very low sodium intake, or any number of other factors, they may become hyponatremic (low sodium) after only 2 hours of exercise. Sodium is definitely the electrolyte that is lost fastest and the only one that really needs to be repleated in the shorter amount of time.

    Potassium is only found intracellular, which means our body can regulate it better – sodium is found intra AND extracellular, meaning our bodies try to balance it between the two. If sodium becomes low extracellularly (in the blood stream and around the outside of the cells) because perhaps the person is only drinking water for replacement plus they’re sweating a lot of salt out, then sodium becomes low extracellularly and to equalize, the body takes sodium out of the cells.

    Sodium is necessary for contraction of muscles, including the heart muscle, and many people will actually become hyponatremic without even noticing the side effects – which can be very dangerous. New studies have just come out on this subject and as soon as I get the ppt from the conference I went to, I’ll send them to you!

    So, with that said, I would recommend drinking eletrolyte drinks if you will be exercising for longer than 2 hours. This can help kill two birds with one stone, so to speak, since many of these drinks also have carbohydrates in them that can help fuel the body on these longer exercise bouts and help prevent hitting the wall.
    Rachel recently posted..Irish Beef StewMy Profile

    • Jason says:

      In the book Runner’s Diet it is there. I will photocopy it and pdf send it to you for you to read and not spend any money on the book.

      Shoot me an email with your fax number.

      I am going to read your milk article now, and thank you so much for your corrections. I am learning weekly from you. Might hire you as the CTER nutritionist. Salary of $0?

  8. Emily says:

    I use nuun during longer workouts. Which, in my very uneducated mind, I believe has electrolytes. And if it doesn’t, then it’s tricking me into thinking it does and helping me rock out.
    Emily recently posted..When the Going Gets ToughMy Profile

  9. Scott says:

    What I like to do in the summer, since I start to get sick and tired of drinking sport drinks and GU’s, chomps, the whole nine yards. I like to sprinkle a touch of salt on watermelon, in my opinion, its a great recovery combination

  10. Jen says:

    Great article. I’m always confused on what to drink/fuel with on long run days (2+ hours…)

    I tend to stick to water when I run shorter distance and switch to sports drinks for longer runs. (though I hate the taste too…)

    I get cramping too – unfortunately, I discovered about a year ago that I have a banana intolerance =( it was a sad discovery.
    Jen recently posted..Film Festivals- Cupcakes and DeterminationMy Profile

  11. Chris says:

    Hadn’t heard the bit about less salt when not training before. Interesting and definitely warrants further research on my part.

    I have a banana a day, Hammer Heed during workouts, and Hammer Recoverite after tougher/longer efforts. On light days I may bring water and Clif ShotBloks instead. I sweat like a pig so I’m basically a big pile of salt when I’m done.
    Chris recently posted..Week in ReviewMy Profile

  12. Bob says:

    I go into this in detail in my book. First you need to calculate exactly how much fluid you lose during training under different weather conditions. Next you need to determine the level of “salter” you are. That would be the level of sodium (and other electrolytes) that is in your sweat. With that data, when you race, under any weather condition you can determine how much water and electrolytes to use need to replace. To simplify matters I use INFINIT and SALTSTICK. These two things in proper levels (depends on weather) with the proper water supply is all you need for carbs, protein, amino acids, electrolytes and calories.
    Bob recently posted..SELF DOUBT IS GOODMy Profile

  13. Jeff Irvin says:

    Problem for us is that about 50-60% of our races are on the bike. How do I carry a banana on the bike and eat it while racing? This is where supplements make sense.

    Gels – EFS Liquid Shots 1500mg electrolytes.
    Drink – EFS Drink – 1160mg of electrolytes per serving.

    Why drink Gatorade or GU/Hammer AND still carry salt tabs when you can take these? Big fan of the KISS method for racing and training (Keep It Simple Stupid).
    Jeff Irvin recently posted..When Bad Workouts Stopped My Profile

  14. lindsay says:

    reading as i eat salty rice works chips…. :) mmm salt. i am still working on eating healthy dude, can’t go confusing my brain with tracking specifics just yet! ;)
    lindsay recently posted..dear speed- be my friendMy Profile

  15. MCM Mama says:

    I’m borderline addicted to nuun. I find that it makes a huge difference on a hot run, but that may also be because it gets me to drink more than straight water does.

    I’m about halfway through that book right now. I’m finding it very informative.
    MCM Mama recently posted..Im doing it for the environmentMy Profile

  16. caroline says:

    EFS Liquid Shots for me
    so far the best thing I have tried.
    caroline recently posted..Half wayMy Profile

  17. Karyn says:

    love this post. very comprehensive. i like to eat my electrolytes, bananas are my best friend. as is the salt shaker hahah. but i never really think to replace them after hard sessions. i guess i just naturally gravitate towards foods (and added salt)

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