While EFS & EFS-PRO EFS drinks both combine the latest clinical research and technology and are both designed as complete hydration and fueling drinks that can be used keep you fueled and hydrated at any distance, there are times when it’s best to use one instead of the other. One of the great things about both EFS and EFS-PRO is that you never will need to take additional electrolyte pills/tablets with either formula.
EFS DRINK MIX: 
Fluid loss plays a major factor in performance. Studies show that when you lose 2-3% of the body’s fluid through sweat, performance decreases by up to 7%. This can be the difference between winning and not even finishing. Electrolytes promote the absorption of water during exercise. When you sweat, you lose essential electrolytes, which can result in cramping and dehydration. The transfer of nutrients and water in and out of the cell known as cellular respiration requires all five electrolytes in a precise balance for maximum cellular efficiency. EFS delivers 1160mg of electrolytes to keep you hydrated, prevent cramping and maximize endurance.
EFS is the first endurance drink to be fortified with clinically effective doses of the amino acids Glutamine, Leucine, Iso-leucine and Valine. These key amino acids have been shown to improve glycogen re-synthesis and delay central (mental) fatigue. The latest research reveals that it’s these specific free-form amino acids that are inherent in protein, not the complete protein itself, that improves glycogen resynthesis and delays central (mental) fatigue. The benefits of using free-form amino acids are that because they’re small molecules they are much easier to digest and absorb while exercising, they don’t cause bloating and they don’t cause GI distress.
EFS BENEFITS:
- Contains all 5 Electrolytes in the levels endurance athletes require to prevent cramping and dehydration
- Eliminates need to take additional electrolytes
- Improves glycogen resynthesis and delays central fatigue
- Contains easy to digest free-form amino acids
EFS-PRO:
EFS-PRO was developed to meet the unparalleled requirements of professional athletes so they can push the limits of endurance in ultra-long training and racing, excess heat and other extreme conditions without compromise. EFS-PRO delivers more calories, electrolytes and other essential nutrients than any other endurance drink mix.
EFS-PRO delivers a proprietary blend of carbohydrate sources that each offer unique benefits for endurance athletes. These special carbohydrates work synergistically to achieve optimal performance through varying channels of absorption. The primary carbohydrate used in EFS-PRO is a branched chain cyclic cluster dextrin (CCD) that’s high-glycemic and have very little effect on insulin. This means athletes are able to sustain hard efforts through the increased use of fats, which allows them to spare essential glycogen. At 150 mOsm, cyclic dextrin is the lowest-osmolality carbohydrate source available and has been clinically proven to have the fastest gastric emptying time of any carbohydrate. This low-osmolality and superior gastric emptying times means athletes can be assured what they drink goes directly to working muscles immediately. Because of this, EFS-PRO can be mixed at stronger concentrations and still be absorbed properly.
This means you’ll have the energy you need, when you need it most, because you’ve been able to burn fat and spare essential glycogen. CCD is one of the lowest-osmolality carbohydrate sources available. It’s also clinically proven to have the fastest gastric emptying time of any carbohydrate. So EFS-PRO can be mixed at stronger concentrations and still be absorbed quickly and easily without causing GI distress. EFS-PRO can be mixed at varying strengths shown in the chart below. 
EFS-PRO is 100% soluble in water and won’t clump or thicken when mixed. This is a great indication of how it get’s absorbed in the stomach.
EFS-PRO was designed to taste like flavored water, eliminating the dreaded ‘sugar-fatigue’ commonly found with other sports drinks. EFS-PRO also delivers a special blend of sodium chloride and sodium citrate that has been shown to improve mineral absorption at high doses. Fortified with L-Alanyl L-Glutamine for enhanced nutrient and water absorption along with these two sodium sources provides the optimal electrolyte shuttle for racing in hot environments.
*In extremely HOT conditions, we recommend you use EFS-PRO (instead of EFS) exclusively.
EFS-PRO is ideal for athletes who have a sensitive stomach, are prone to cramping or are training or racing race in extreme heat.
EFS-PRO BENEFITS OVER EFS:
- Delivers more electrolytes
- Delivers more carbohydrates
- IDEAL IN HOT CONDITIONS
- Easier to absorb and digest
- Lite flavor & Lower in sweetness
When will the new EFS be avail
Hi Clint,
We hope to have it available in approximately 2 weeks! It’s a significant upgrade.
I’m doing IM 70.3 WI on June 9th. Predicted weather is 73-77 degrees. I’m guessing I’ll be on the bike around 8:00 a.m. give or take when I get in the water.. Start is 7 am. I know what I’ll need to do for the run but I’m wondering about hydration on the bike. What I have been doing in training is 1 scoop of EFS in a 25 oz, or 32 oz bottle that I consume within 1 hour. i.e. nutrition before start of bike, First hour Is mainly water and a gel. Then I start sucking in the EFS bottle. Every hour I have a bottle of EFS available. I would guess Ill be on the bike around 3 hours maybe a little less. Recently I’ve tried putting in 2 – 3 scoops of EFS into the bottles and having them ready.
How does this affect osmolality? What is the best course of action?
I was thinking of going with EFS PRO for the bike. Or would EFS be fine with extra scoops?
Hi, I am wondering if it is okay to mix EFS Pro with EFS Drink mix (I prefer the EFS drink mix flavor). Any suggestions on mixing strengths?
Thanks
Yes you can absolutely mix these two together. How you mix really depends on you and if flavor is a main determinant then the best flavor will give you the highest probability that you will drink it and really this is the best scenario. I’d start with 1:1 and adjust from there.
Hi, I’m going to hike the Grand Canyon, Rim to Rim to Rim to Rim. The map claims 65 miles and 30k feet elevation total change. I won’t be running, but hiking at a fast pace non-stop, for 35-40 hours.
How would I use this product, how much/what quantity, at what intervals? And would I need any other nutrition or supplements? And how many containers/bottles would I pack for this challenge?
Thank you!
Rad,
Congratulations on taking the huge step to go accomplish this amazing feat. We’ve had a couple of our top professional trail runners do the RRR in past years with great success. Of course they are running with the goal of establishing the fastest known time. For your attempt, how much EFS to use really depends on how you plan to support your effort. EFS or EFSPRO is capable of being our sole calories for this entire endeavor, though I suspect you will likely be bringing other food and calories. IF you are using EFS or EFSPRO as a supplement to your other calories, I would look at this product as a way to ensure you are properly hydrated and have the electrolyte balance needed to function at a high level. About one serving per 1-2 hours would be appropriate for your adventure. This means 20-40 total servings of EFS and you would then need to supplement with other calories.
43 yo Male Criterium racer. Sensitive to sugars and cramp easily. I’m interested in EFS-PRO and wondering how you would recommend I take it for fast, intense interval racing for an hour in Utah?? Any other products for recovery etc..? Beet powder for NO..??
Thank you so much..!
Evan,
We do believe EFSPRO can help with your criteriums. Since the race is so short, its best to pre-hydrate and get the balance of 5 electrolytes in before your race. Consume a full serving for the hour before your criterium and a 2nd serving during the race. A mix of 120cal in an 18-22oz water bottle should suffice.
For NO support, try our PreRace product. We use citrulline malate as the primary driver of NO stimulation due to its extensive data.
Help!
Im 43 yo male, 180lbs and very lean/fit. I race criteriums which are high intensity interval races for about 50 minutes on average. I cramp often and get fatigued quick. I have a sensitive stomach and don’t do well with goo and sugars due to candida and Lyme’s issues. My training and nutrition have improved but I’m wondering if EFS Pro could help me during the hot summer races? If yes, How would you recommend I take it? Any other products that might work well synergistically? Do you have a beet powder for NO support also?
Thank you for any suggestions..!!
Aloha From Hawaii,
Just started using EFS Pro, ride about 120 to 180 miles a week in 85*f to 90*f. I use 500ml bottles and would like to know the optimal amount of EFS Pro to use/scoops per bottle? My assumption is 4/500 ml bottle ??
France,
THank you for your question. Your calculation is pretty accurate and for most situations 4 scoops per 500ml is just about right. EFSPRO can be used as a high hydration formula as well where you would mix 3 scoops in 500ml. IF you are going super long and need additional calories, due to its low osmolality it will also absorb well at 5 scoops per 500ml and will obviously deliver more calories.
My daughter is 15 y.o., playing tennis, training 4hrs a day + 1hr fitness. She sweets a lot, during the practice and tennis matches. She is using Gatorade with Endurance pack. I am thinking to switch her over to EFS Pro. Is it safe for the kids of this age? Will EFS Pro supply her body with enough electrolytes and energy? I am not sure if I need to switch from Gatorade? Please advise
Alex,
Yes it is safe to use. She will be well served by either EFS or EFSPRO as both deliver an effective dose of electrolytes and amino acids. The EFSPRO takes it up a notch for those super hot days.
Thank you. I will probably stick with EFS. How much (oz) she can drink during 4hrs of practice? Right now, she drinks three to four bottles of regular Gatorade in 4 hrs (total about 80oz) plus two bottles of water. She sweats a lot. Please advise
Alex,
It depends on the heat and intensity of her workouts. 12-24oz with 100-200 calories of EFS should suffice for her tennis training and matches.
I’m trying to find information on whether EFS/EFS-PRO are safe for children, and if so, do you have recommended mixing ratios by weight? Thanks in advance!
Bob,
We don’t recommend any of our products for children simply because these are designed and researched on adults. EFS and EFSPRO are made with natural ingredients, have no artificial colors or flavors and are simply a combination of carbohydrates, amino acids and electrolytes. If you feel comfortable giving this to an athlete, then its up to you. Again, because we don’t push or market our products to children, we really don’t offer up recommendations, however you can use common sense to determine appropriate mix for a child based on size/weight..etc.
Is there any chance I could see a nutrition label for EFS Pro as well as mixing instructions? Thanks! Katie
Yes, its on our website. Click on ‘ingredients’ in the middle of the page.
https://firstendurance.com/nutrition/efs-pro/
Hi, any suggestions or strategy for this?
On December, I’m going to run “El cruce de los andes – Columbia”, this is a trail race with 3 days to complete 100 kms (63 miles), my training days until that date are around of 2.500 to 3.500 calories per day (week 3 hours per day – 4 days) – weekend 5 hours per day – 2 days), the weather is between 30 -34 celsius aprox.
After a hard day (weekends), I use Ultragen to recover me but during training I just drink water and eat cooked potatoes to get carbs, and some milkyways to get energy (I hate energy gels due to stomach effects).
Any advice? EFS Pro?
Pablo,
Thank you for your comment. Due to the high temperatures, this is a perfect situation to use EFSPRO. Start by substituting your potato calories with EFSPRO.
So if I am a very heavy sweater and like to consume about 350 calories an hour on the bike how would I mix Efs pro to a 20-24 oz bottle…
Also on the run, how would I use liquid shot to make it adequate being a flask is 400 calories ? Thanks in advance
Les Carr,
In short, you don’t. You don’t because the osmolality of this and any other nutrition would be too great. Check out this article which explains it.
https://firstendurance.com/fueling-strategies-hot-days/
Hi! Love the taste of the product. I race marathon+ MTB races and have a few questions
(1) Do you know if there is any research to suggest that women should consume more or less than the recommended dose? Or, should small people take smaller doeses (I’m about 54.4kg).
(2) Over the course of a 3+ long effort, is it okay to supplement EFS Pro with EFS liquid shot? Or would that be a sugar overload (assuming I consume 3 scoops in 24 oz)?
Appreciate the advice!
Bella,
These are great questions.
1) Yes you can consume less. We answer this based on research in this article. https://firstendurance.com/why-do-women-burn-fat-differently-than-men/
2) Yes you can consume EFS Liquid Shot with EFSPRO, however it may not be the best approach. We answer this here. For the record, there is no real basis to concern yourself with sugar overload if you consume enough water. https://firstendurance.com/fueling-strategies-hot-days/
I’m a long-time EFS user and I have two situations to ask about. First, I compete in cycling time trials / relay triathlons of 40 to 50 minutes duration. I would prefer not to take any bottles on the bike for these races. Which product(s), mix, and hydration strategies would you recommend? Is it possible to “preload” my hydration by consuming it before the start of the race? Second, when I do sustained above-threshold efforts on the bike (as in an FTP test), I tend to feel a heartburn-like sensation about 10 minutes into the effort. This sensation holds me back. Is there any strategy / product I can use to minimize or eliminate this problem? Thanks!
Bill,
Great questions. For a 40-50 minute effort you do not need any fuel if your glycogen is topped off. Pre-hydrating would be a great strategy to make sure you are ready for that effort. Taking a full serving of EFSPRO 30-60 minutes prior to your effort would definitely suffice. For your FTP efforts make sure you are well hydrated (electrolytes and water) but have no calories in your stomach. Again a protocol where you have an EFSPRO 30-60 minutes prior to your FTP would be the way to go. During the FTP warm-up you could sip on water.
Hi,
I used to ride in Miami, 3 to 3h30 hours in the morning at 75 to 81 F, using 2 x 24 oz of EFS (2 scoops) and 1 to 2 others 24 oz of water.
Do you thing it s better to go to EFS PRO?
Do you thing I can take 3 to 4 x 24 oz of EFS without intestine issues ?
thank you for your answer
Marc,
EFSPro will be easier to absorb and will drive more electrolytes into the muscle. If you’ve found issues with cramping or gastric distress, then definitely try the EFSPro. If the EFS has worked for you with no stomach issues or cramping you can stay with that product. Concentrations of 100cal per 12oz are well tolerated so you should have no issues as long as you stick to this concentration.
What’s the osmolality of EFS?
To avoid the excess sweetness, could you use 1 scoop of EFS in a 20oz bottle without an osmolality issue?
James,
Great question. The concentration of a drink affects its osmolality. Making a drink more dilute means you have lowered its osmolality, so there is no issue doing this. EFS at full concentration (32g in 12oz) has an osmolality around 390, whereas EFSPRO at the same concentration has an osmolality around 250.
Looking for options for hydration. I tend to loose about 2 Lb/hour on sweat (in cold weather) and have sensitive stomach. I tried tablets and other hydration solutions but still feel full stomach by the run leg of my triathlons. I have been recommended to drink 32oz hydration solution with 100-150 cal/hour. Any sugestions?
Angel,
You’ve come to the right place. A full stomach is likely an indication that what you are consuming is not getting absorbed. We suggest you stick to a program that is all liquid calories and that you only consume electrolytes, carbohydrates and water. Leave the gummies, bars and other nutrients at home for snacks. 32oz of hydration and only 150 calories per hour is not ideal as this is quite low on calories to sustain someone for a long event. If the event is 3 hours or less, this might be OK, but if you are going longer you will need more calories. The article below will give you the guidance you need to maximize energy and hydration.
https://firstendurance.com/fueling-strategies-hot-days/
Is EFS Pro and other EFS products sold or carried by any bike shops or tri shops in the greater mesa and Phoenix area? So far, Ive tried EFS and really like it.
I would like to try the other products as well.
Hi Fred, EFS-PRO is only available via http://www.firstendurance.com. If you sign-up for our VIP/Rewards program, you’ll get 20% off your first order plus free shipping on any order over $49.