We spared no expense upgrading the EFS drink mix, investing in the latest research-driven innovation and technology. The new isotonic formula delivers complete nutrition that supports physical and mental performance, redefining the limits of endurance nutrition so you can redefine your limits of endurance.
INDUSTRY-LEADING ELECTROLYTE LEVELS TO PREVENT CRAMPING
We know how frustrating it is to have your day wrecked because you’re seized up with debilitating muscle cramps. It’s the number one issue most athletes face. That’s why we engineered EFS.
Unlike most hydration mixes, EFS delivers a clinically effective dose of all 5 electrolytes (sodium, potassium, chloride, calcium, magnesium) in the levels shown to prevent cramping.
A NEW WAY OF THINKING
The latest EFS formula is a breakthrough in sports hydration. With more electrolytes than competitors and ingredients to improve mental focus, you’ll finish the race as strong as you started
The brain plays an essential role in endurance and performance. Mental toughness and presence of mind are equally as important as fitness. You have to be able to suffer and handle stress when your body is begging you to stop.
That’s why the reimagined EFS includes Suntheanine ®, a patented innovation that gives you the mental toughness you need to push further and find a gear you didn’t know you had.BUY NOW
Definitely love the new flavors of EFS
Suntheanine® boosts mental toughnessto help you push through suffering
7% osmolalityensures bioavailability and reduces GI distress
Prevents cramping and dehydration—delivers 1160mg of electrolytes
Citric and malic acidspromote oxygen uptake and energy production
Carbs from multiple sourcesprovide immediate and sustained fuel
New taste profile eliminates the flavor vs function compromise
The new EFS drink mix tastes great, helps keep you focused during long and hard training sessions, and fuels the body properly
A SYSTEM THAT PUTS ENDURANCE FIRST
EFS is for use during exercise to prevent cramps, maintain fuel levels, and support mental toughness when it’s needed most. It can be supplemented with Liquid Shots before and during an event, and Ultragen helps consolidate gains during recovery between sessions.
Regardless of your training load, a daily dose of our MultiV and Optygen lines help you lay a foundation to achieve your goals.
BIOAVAILABILITY IS THE BEST ABILITY
From the carbohydrates (osmotically balanced with your body in a 7% solution) to the electrolytes (20-100% better absorption rates), every ingredient in EFS is selected and portioned for faster and easier absorption without GI distress.
The inclusion of citric and malic acids also encourages oxygen uptake and production of ATP (the body’s energy source), helping your cells use the fuel once it’s delivered.
PREMIUM INGREDIENTS FOR PURITY AND PURPOSE
We prioritize purity by using only Suntheanine, the original and cleanest L-theanine, and free-form amino acids, which have a purity level of 99-100%.
We also omit ingredients with no value—even the ubiquitous vitamin C, which features in virtually every other mix despite research that shows it reduces endurance when taken during exercise. EFS still provides immune system support courtesy of theanine, just without impacting performance.
NO RESPECT FOR THE STATUS QUO
Our approach to product design eschews unexamined ingredients, traditional processes, and trendy minimalism in favor of research-based innovation, premium ingredient sourcing, and the uncompromising expectations of elite athletes. We’re always ready to show our work and support our products with the scientific literature that informs our design choices, but we also know what virtually every athlete and publication using or reviewing our products learns firsthand: First Endurance products speak for themselves, and you can feel the difference right away.
Q: How much EFS should I use during my training and racing?
A: Clinical research shows that a 6-8% solution delivering between 45-60g carbohydrates, >1000mg amino acids, 400-600mg sodium and equivalent balance in all electrolytes should be taken every hour during exercise. Athletes should consume one serving for every 30 minutes of intense exercise. Adjustments should be made based on body weight, training state, heat, individual sweat rates and preference. Use one serving for every 30 minutes as a starting point and adjust as necessary from there. Additional calories and electrolytes can be added with Liquid Shots.
Q: Are there other benefits to drinking EFS, besides for training and racing?
A: Absolutely. EFS can be used to top off electrolytes and help you calm down so you can get a good night’s sleep the night before (or two nights before) an event or race. When you’ve invested an entire season’s prep in peaking for a specific day, the calming effects of EFS can help ensure restless nights leading up to that day don’t undercut your form.
Q: Do I need to take a full serving of EFS to get a benefit?
A: No. A higher concentration increases calories and electrolytes. While our recommended serving concentration is designed to maximize theanine’s effects in a steady dose, ingesting reduced amounts will still produce a proportionally scaled effect in terms of promoting calm focus. In other words, if you are a smaller person and normally consume a somewhat reduced amount, you will still get the same benefits.
Q: How should I mix EFS?
A: USE DIRECTIONS
SMALL SERVING: Mix 1 scoop with 21-22oz of water
LARGE SERVING: Mix 1 ¼ scoop with 24-26oz of water
BEFORE: Consume 1 bottle 30 minutes before exercise.
DURING: Alternate 1 bottle of EFS and 1 bottle of water every 30 minutes.
TIP: For additional calories and electrolytes, double the concentration or supplement
with Liquid Shot.
Q: Is there any way to get too much Theanine from EFS or EFS-PRO?
A: Only if you macro-dose (200mg or more in a single or repeated shot). Even if theanine is administered in a single macro-dose, the effect is just a too-calm calm that fades as the theanine leaves your body—Nothing serious or harmful. Click here to learn more about dosing and uptake. Since our EFS or EFS-PRO serving is limited to a gradually administered 80g every hour, you won’t hit that dose of theanine, even with continued use as directed. That’s because theanine is water-soluble, it metabolizes fast and doesn’t accumulate . Once ingested, it’s half gone after 60-90 minutes, and it’s gone completely in 24 hours.
Q: Does EFS or EFS-PRO help me hydrate better than water?
A: We won’t name them, but there’s a growing list of competitors in the sports hydration game making the claim that their product hydrates better or faster than water alone. This is a so-what claim predicated on evidence that not only doesn’t apply to endurance athletics, but actually hampers performance during long-term endurance events. For their rationale and claims support these companies cite WHO and other medical guidelines for treating serious dehydration in disease and severe exposure conditions, not the sports nutrition guidelines for healthy athletes in endurance competitions. Also important is the need for more fuel, and these drinks fall short in the fuel department. Check out Dr. Bucci’s extended consideration of these claims here.
Q: I’ve heard that there are benefits to having protein during exercise. Why doesn’t EFS contain protein?
A: EFS contains 2g free form amino acids per serving which is the equivalent in BCAA and glutamine profile to 9g whey protein. Protein naturally contains BCAAs and glutamine.
Clinical evidence supporting the use of BCAAs and glutamine during exercise dates back to 1991. These clinical studies clearly indicate supplementing with as little as 1g free form amino acids improved performance, reduced post-exercise muscle damage, improved muscle glycogen resynthesis, reduced central fatigue and improved rate of perceived exertion. These are the same claims made by the most recent protein study and clearly support a mechanism for improved performance.
In addition to the clinical support, other factors lead to a decision to use these free form amino acids over complete proteins.
Proteins are more difficult to digest than amino acids during exerciseProteins don’t taste very good during exerciseProteins can reduce the glycemic index of a drink, further reducing its ability to be quickly absorbedThere is considerably more evidence supporting free form amino acids than complete protein
Q: I am prone to cramping during longer training and racing. Will EFS help me with cramping problems?
A: Nutritionally, cramping stems from electrolyte imbalance, electrolyte depletion and/or dehydration. EFS provides the most potent electrolyte profile available. The combination of all five electrolytes delivers a potent 1160mg per serving, helping to prevent cramping. The 300mg sodium per serving also aids in maximum fluid absorption so you stay hydrated throughout your training and racing. Supplementing with additional salt tabs, electrolyte tabs, or salty snacks is no longer needed when using EFS.
Q: How should I use EFS/EFS-PRO for races or training that lasts more than three hours?
A: New research suggests athletes can ingest more and more carbs per hour. For detailed information, check out this blog.