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Refuel faster and last longer.

With First Endurance’s EFS Energy and Endurance Drink Mix, you don’t need to worry about cramping or dehydration during intense training. EFS’s formula delivers over 1,000mg of all five electrolytes and is fortified with clinical doses of important amino acids to boost glycogen re-synthesis and delay fatigue. Also, three different high-glycemic carbohydrate sources provide you with quick energy and increase stamina.

  • Provides over 1,000mg of all five electrolytes
  • Clinical doses of the amino acids glutamine, leucine, iso-leucine, and valine
  • Three different high-glycemic carbohydrate sources

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Here's what others have to say...


new to using, but like so far

  • Familiarity:I've used it once or twice and have initial impressions

Used this for my first half ironman a couple weeks ago. I alternated a bottle of water with a bottle of grape EFS in water during the bike leg and felt great. Definitely plan on using more and getting more familiar with it.


solid nutrition & tastes good

    First Endurance EFS in the grape flavor is one of my favorite nutrition products for cycling. This product not only provides hydration but energy (calories) too. I’m not an expert but the ingredients look good and it definitely tastes great. The grape flavor is extremely mild. Obviously, that’s why they call it “mild grape”. It’s not too sweet and I’ve never had any cramping with it. It’s also fairly economical compared to similar products. On long rides in hot weather I typically fill one bottle with this and the other with Skratch hydration mix.


    It works, but the taste could be better.

    • Familiarity:I've used it several times

    I used EFS for a 152 mile bike ride that I did over the summer. Great product, definitely keeps you from having cramps. It is not as smooth as some of the other drinks as far as flavor goes.


    It works but why the taste?

    • Familiarity:I've put it through the wringer

    I continue to purchase and use this product because it simply works better than any other endurance fuel powder on the market. That being said, why oh why does it have to taste like a concentrated dose of smashed up smarties? If you're looking for something that works, buy this, but be weary of the taste.


    Sweater's Delight

    • Familiarity:I've put it through the wringer

    When I'm on the bike in the summertime I sweat like a (insert crude joke here). The amount of electrolytes in EFS keep me from cramping up on long rides while I'm losing all the fluid in my body. A year or so ago they changed the formula & the lemon lime which used to be my favorite flavor became a bit too tart for my liking. After trying the Fruit Punch (too sweet) I've settled on the Orange as my new drink of choice.


    Great product

    • Familiarity:I've put it through the wringer

    When it comes to these types of drinks I've tried them all, to find the best one for me. EFS I think is spot on, with their product. Works well, I tend to feel a little more endurance and I don't cramp as much.


    Really Works

    • Familiarity:I've used it several times

    The stuff really does work. I have been taking the lime one and i don't think there is much of a taste. Add some liquid shot in the drink, and BAM... your away.


    Effective but kinda gross (lemon-lime)

      The lemon-lime tastes pretty gross, but it's the only one I've had so I don't know how the other flavors are. It doesn't have the carbs and calories of CarboRocket (which I'm going to stick with) so you definitely have to supplement with bars, gels, or whatever. I'm sure its electrolyte are great, but the taste is pretty nasty, especially when it warmed up on a hot ride.



        I love this stuff, i was previously using carboroket but i like the stronger taste of this better than the very subtle taste of other drinks like carboroket or hammer, but then again my stomach handles about anything.

        keeps my legs feeling good while riding and I dont ever gets cramps after


        Better than Gatorade!

          This stuff is solid as an electrolyte replacement. I'm partial to lemon/lime flavors and this one is pretty good. Not as sweet tasting as OG Gatorade.


          Like it.

            Helps me avoid cramps. Pretty salty, wife can't stand it. Bland and I like that.


            Great Hydration

              I'm a big fan of First Endurance products. The energy and endurance drink is key for long rides, replacing electrolytes. I have been on rides where my friends are bonking on climbs and I'm still motoring on. I partially attribute this to staying hydrated with a product that is designed to keep your motor running. The flavors are pretty good. I'm partial to the fruit punch and grape flavors but I'm not a huge fan of the lemon-lime.


              First Endurance EFS Energy and Endurance Drink Mix

                First Endurance make great products. I like their range of flavours in drink mixes. I honestly think this helps me stay better hydrated in races, and it contains some very helpful nutritional products like glutamine too.


                Pretty OK

                  I like the tast of the EFS mix. With higher temperatures I combine it with 1 bottle of water to avoid stumach problems. But in Holland I would just race and train with the First Endurance Drink Mix.

                  First Endurance EFS Endurance Drink.

                  Robert Kunz from First Endurance talks about the benefits of EFS Endurance drink mix.


                  Great mix

                    I usually don't like drink mix and prefer water. But now that the team is using this mix, I have slowly shifted from racing with all water to all EFS mix. It tastes good and doesn't require water to wash it down. It also delivers a few calories per bottle so I can eat one or two less gels per hour when racing.