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EFS-PRO High Carb

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EFS-PRO High Carb is a next-generation fuel and hydration mix designed for endurance athletes pushing through long, demanding sessions. Built around advanced carbohydrate technology and clinically effective electrolytes, EFS-PRO delivers scalable fuelling from 30g up to 120g of carbohydrates per bottle while remaining easy on the stomach.

  • Delivers 60g carbohydrates per serving with scalable fuelling up to 120g per bottle
  • Uses Cyclic Cluster Dextrin for fast absorption and reduced GI distress
  • Supports sustained energy production during long endurance sessions
  • Clinically effective electrolyte blend helps maintain hydration and prevent cramps
  • Isotonic formula designed for fast uptake, even at higher carb concentrations
  • Light, natural flavour profile reduces flavour fatigue during long efforts
  • Vegan and gluten-free formula

EFS-PRO High Carb

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£49.99
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How to use?

Mix one serving with water and use before or during long endurance sessions to support energy and hydration.

Calculate how much you need here

When to use?

Ideal for training or racing lasting longer than two hours, especially in hot conditions or during high-intensity efforts.

Why do I need this?

EFS-PRO helps you increase carbohydrate intake while reducing the risk of stomach discomfort, dehydration, and energy crashes during demanding sessions.

Who uses this?

Used by endurance athletes including runners, cyclists, triathletes, and ultra-distance competitors looking for high-carb fuelling with reliable hydration support.

Description

At the centre of the formula is Cyclic Cluster Dextrin (CCD), a highly digestible carbohydrate source chosen for its fast absorption and low GI stress. Combined with sucrose in a carefully balanced ratio, EFS-PRO supports efficient carbohydrate delivery while helping reduce the stomach discomfort and flavour fatigue that often come with long-duration fuelling. The formula is engineered to keep energy levels stable, preserve glycogen stores, and support sustained performance deep into training or racing.

EFS-PRO also delivers a clinically effective blend of electrolytes including sodium, potassium, chloride, calcium, and magnesium to support hydration and help prevent cramping in hot or high-intensity conditions. Unlike many traditional sports drinks, it is formulated to remain isotonic even at higher concentrations, helping fluids and carbohydrates absorb quickly when your body needs them most.

Naturally flavoured and free from artificial sweeteners, colours, and stevia, EFS-PRO has been designed with long-term usability in mind. The light, refreshing taste makes it easier to stay consistent with your fuelling plan over several hours, while the minimalist ingredient profile focuses only on what supports endurance performance.

How does it work

EFS-PRO works by combining multiple carbohydrate sources with advanced electrolyte support to maximise fuel delivery while remaining gentle on digestion. The formula uses Cyclic Cluster Dextrin as its primary carbohydrate source, which has a high molecular weight and low osmolality. This allows it to empty from the stomach quickly and absorb efficiently without causing bloating or heaviness, even at high carbohydrate concentrations.

Alongside CCD, EFS-PRO includes sucrose to support multiple carbohydrate transport pathways, helping the body absorb and utilise more fuel per hour. This dual-carb approach increases carbohydrate availability for ATP production while maintaining stable blood glucose levels and supporting glycogen preservation. Added electrolytes such as sodium, potassium, magnesium, calcium, and chloride help maintain fluid balance, muscle function, and hydration throughout prolonged exercise.

Nutrition

18 Serving Pouch (1150g) / Sour Watermelon

Serving Size: 2 Scoops (64g)

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Serving Per Container: 18

Amount Per Serving
Calories 240kcal
Fat 0g
Carbohydrate 60g
- of which sugars 15g
Sodium 380mg
Magnesium 75mg
Potassium 165mg
Calcium 75mg
Chloride 420mg

Ingredients

Directions of use

Mix one serving of EFS-PRO into 500-750ml of water and consume before or during exercise. Adjust serving concentration based on session duration, intensity, and carbohydrate needs.

About First Endurance

First Endurance has been redefining endurance nutrition for over 20 years with clinically effective formulas trusted by elite athletes. From fuelling to recovery, every product is designed to help you perform at your best.