PERFORMANCE REDEFINED

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

PATENTED TECHNOLOGY

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

Tina Pic Pro Cyclist & 6x USA Criterium Champion

PERFORMANCE BENEFITS

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

Matt Hanson5x IRONMAN / 5x 70.3 Champion / Holds the record for the fastest full-distance IRONMAN (7:39:25)

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.

RESEARCH

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.

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