EFS-PRO utilizes the latest research and technology to meet the unique requirements of elite athletes in the most extreme conditions.

✓ Professional Strength Endurance & Hydration Drink
✓ Provides more calories & electrolytes than traditional drinks
✓ Delivers steady, long-lasting energy without GI distress

Expires 3/31/21





EFS-PRO delivers more calories, electrolytes and other essential nutrients than traditional drink mixes. You’ll notice the difference right away. With the latest innovations and technology available, EFS-PRO helps you excel when everyone else is falling apart.

The primary carbohydrate used in EFS-PRO is a branched chain cyclic cluster dextrin (CCD) that’s high-glycemic and has little effect on insulin. 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.

Once you try it, you’ll never settle for anything else.


Clinical research shows endurance athletes require much higher levels of electrolytes than most sports drinks provide in order to prevent cramping and dehydration.

Each serving of EFS-PRO provides 1400 mg of the essential electrolytes endurance athletes need to stay hydrated and maximize performance.



EFS-PRO delivers a proprietary blend of carbohydrate sources that each offer unique benefits for endurance athletes. These sources work synergistically to achieve optimal performance through varying channels of absorption. The primary carbohydrate used in EFS-PRO is an amylopectin multi-branched cyclic dextrin that’s 100% soluble in water. It’s a high- glycemic carbohydrate that has little effect on insulin and does not inhibit fat oxidation.

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 low- est-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 mean athletes can be assured that what they drink goes directly to working muscles immediately. As a result, EFS-PRO can be mixed at stronger concentrations and still be absorbed properly.



Sodium citrate is absorbed and metabolized into sodium bicarbonate which creates an alkaline solution that reduces stomach acidity and improves absorption. Alkalizing agents have also been shown to improve performance in high-intensity exercise. Sodium citrate has been clinically shown to have the best absorption rates among vari- ous sodium sources. A clinical study done on Sodium Citrate showed that when it was consumed prior to high-intensity exercise it reduced blood pH and oxygen debt in healthy males exercising on a cycle ergometer.


EFS-PRO contains L-Alanyl L-Glutamine because it’s clinically proven to significantly improve absorption of water and electrolytes in athletes under exercise stress and mild dehydration and improve endurance performance.

This special dipeptide amino acid is a highly-soluble, water-stable source of glutamine that has a number of unique benefits for endurance athletes. Like L-Glutamine, this dipeptide plays a role in the supply of energy, promotes protein synthesis, heals wounds, pro- motes a healthy intestinal tract and also stimulates immune function.

The alanine component of L-Alanyl L-Glutamine helps stimulate gluconeogenesis (the generation of glucose through non-carbohydrate sources). Clinical studies on L-Alanyl L-Glutamine have shown it improves plasma glutamine by 26% over standard L-glutamine.

In a study done in the Journal of the International Society of Sports Nutrition, L-Alanyl L-Glutamine and water were administered to college students with induced dehydration of -2.5% while a second group used only water. The group using L-Alanyl L-Glutamine showed a dramatic improvement in their hydration and serum sodium levels. This group also significantly improved their performance in a treadmill exercise.


Q: What is EFS-PRO?

A: EFS-PRO is a new energy drink that provides endurance athletes with the nutrients they need to fuel working muscles and increase endurance during exercise. The EFS formula utilizes the latest clinical research on endurance nutrition and input from some of the best endurance athletes in the world.

Q: Why doesn’t EFS-PRO contain Vitamin C?

A: EFS-PRO doesn’t contain Vitamin C because the latest research shows that Vitamin C can have a negative effect on endurance and performance when consumed during exercise. Click here for more info.

Q: What electrolyte can we find in the new EFS-PRO?

A: There is 500mg of sodium per serving in the new EFS-PRO drink (EFS has 300mg). This represents the highest sodium content in any electrolyte drink on the market. The EFS-PRO formula now offers over 1,500mg of electrolytes coming from all 5 electrolytes, per serving.

Furthermore, these superior minerals also offer a buffering of stomach acids. DiCalcium and DiMagnesium malate lower stomach acids significantly helping to reduce the unwanted gastric distress that can be associated with other minerals.

Q: Are there any changes to the amino acids?

A: The amino acids in the EFS-PRO drinks are AjiPure amino acids, the purest, most- bioavailable source of free-form amino acids available. AjiPure amino acids have purity levels of 99%-100%. This results in faster and more complete absorption.

Q: What is the osmolality of the EFS-PRO drink mix?

A: EFS-PRO has an osmolality around 250 when mixed at full concentration (32 grams in 12 ounces of water).

Q: When should I use EFS-PRO instead of EFS?

A: The link below explains when you should use EFS-PRO instead of EFS and visa versa:

Q: What is L-Alanyl L-Glutamine? 

A: The EFS-PRO is also fortified with L-Alanyl L-Glutamine which is a highly soluble water stable source of glutamine with some very unique features. This amino acid has been clinically proven to significantly improve the absorption of water and electrolytes in the intestinal tract.

Q: What is malic acid used for in the EFS-PRO drinks? Why is this important? 

A: The new EFS-PRO drink contains 700mg of malic acid. Malic acid stimulates oxygen consumption by increasing mitochondrial uptake, improving mitochondrial respiration and increasing energy production. Malic acid is essential in the formation of ATP, the body’s energy source. Malic acid allows the body to make ATP more efficiently, even under low oxygen, or hypoxic conditions. During anaerobic conditions, malic acid has an ability to remove the accumulation of reducing equivalents. Human studies have shown that after endurance training, athletes’ muscles were characterized by a 50% increase in the malate-aspartate redox shuttle enzymes.

Q: How is the flavor? 

A: The new EFS-PRO formula went through extensive flavor testing in the most demanding races in the world. We used this extensive feedback to create a flavor profile that mimics flavored water. With practically no sweetness this formula is ideal for those long, hot workouts where sweet drinks simply do not cut it. All formula uses 100% natural flavors and contains NO color. This allows athletes to use EFS not having to worry about staining water bottles.



First Endurance offers everything an endurance athlete needs to maximize endurance and performance.  We designed it to work as a complete endurance system. Each product has a specific purpose and complements the others.

With First Endurance, there’s no more guesswork.