How to Use Energy Gels for Running: A Dietitian’s Evidence-Based Guide

Bonking mid-run? Energy gels are one of the most misunderstood, yet powerful fuelling tools runners use to stay strong when fatigue hits. When used correctly, they can delay exhaustion, support pace, transform long runs and race-day performance. This dietitian-led, evidence-based guide breaks down exactly how energy gels work, when to use them, and how to choose the right one for your run.

What Are Energy Gels & How Do They Work For Runners?
When Should You Take Energy Eels During A Run or Race?
How Do Energy Gels Improve Running Performance & Endurance?
What Types Of Energy Gels Are Available For Runners?
Which Energy Gel Brands Are Most Popular With Runners?
What Should Runners Consider Before Using Energy Gels?
Conclusion: Smart Strategies for Energy Gel Use

What Are Energy Gels & How Do They Work For Runners?

Energy gels provide a concentrated source of rapidly absorbed carbohydrate to maintain blood glucose levels during prolonged running¹,².
Ingesting carbohydrate during endurance exercise supplies exogenous fuel, reducing reliance on finite muscle glycogen stores².
Common carbohydrate sources include glucose, maltodextrin, fructose and cyclic dextrin, which use different intestinal transporters to enhance absorption when combined³.
Some gels also contain electrolytes for hydration, caffeine or other stimulants to reduce perceived effort, and in some cases BCAAs, which have been studied for their potential role in reducing muscle breakdown during prolonged exercise⁴⁻⁶.

When Should You Take Energy Eels During A Run or Race?

Carbohydrate intake is recommended for runs lasting longer than 60-90 minutes¹.
Gels are typically consumed every 30-45 minutes to achieve target carbohydrate intakes during endurance exercise¹,².
Starting carbohydrate intake early in exercise is more effective than waiting until fatigue develops².
Consuming gels with water improves gastric emptying and reduces gastrointestinal distress³.

How Do Energy Gels Improve Running Performance & Endurance?

Carbohydrate ingestion during endurance exercise consistently improves performance compared with water alone¹,².
Benefits include improved time-to-exhaustion, sustained pace and reduced perception of effort¹.
Higher carbohydrate delivery rates (up to 60-90 g/h from multiple transportable carbohydrates) are associated with greater endurance performance benefits³.
Caffeine-containing gels may further enhance endurance and mental focus in some athletes⁴.

What Types Of Energy Gels Are Available For Runners?

Single-source carbohydrate gels¹.
Some gels use multiple transportable carbohydrates, such as glucose–fructose or cyclic dextrin–fructose blends, to maximise absorption by utilising different intestinal transporters, typically in ratios such as 2:1 or 1:0.8.³
Isotonic gels reduce the need for additional fluid⁷.
Electrolyte-containing gels to support hydration¹.
Caffeinated gels for performance support⁴.
Hydrogels to encapsulate carbohydrates and allow them to pass through the stomach with reduced gastrointestinal discomfort⁸.

Which Energy Gel Brands Are Most Popular With Runners?

Commercial gels vary widely in carbohydrate dose, carbohydrate type and caffeine content⁷.
Popular brands used in endurance research and practice include; Precision Fuel & Hydration, GU Energy, Maurten, SIS, Carbs Fuel and Pure Sports Nutrition⁷.
Selection should be based on gender, carbohydrate content, tolerance, taste/ consistency preference and race logistics rather than marketing claims¹.

What Should Runners Consider Before Using Energy Gels?

Gastrointestinal tolerance varies between individuals; gels should always be trialled in training and tailored to individual needs¹,².
Excessive intake or poor fluid pairing can increase GI symptoms during running³.
Energy gels are best used as a targeted supplement for longer training sessions, while everyday carbohydrate needs should be met primarily through whole foods¹.
Fueling strategies should be individualised based on gender, gut tolerance, running intensity and event duration².

Conclusion: Smart Strategies for Energy Gel Use

Energy gels provide fast, absorbable carbohydrates that help maintain blood glucose and delay fatigue during long or intense runs. Used strategically, they can significantly improve endurance performance, however timing, tolerance and individual needs matter. Understanding how to use gels correctly allows runners to fuel smarter, train better and race stronger.

Ash Miller
Dietitian and Nutritionist (Masters)
Bachelor of Physical and Health Education
Instagram: @ashthomo_nutrition

References

Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance. J Acad Nutr Diet. 2016;116(3):501–528.
Burke LM, Hawley JA, Wong SH, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 2011;29(Suppl 1):S17–S27.
Jeukendrup AE. Carbohydrate intake during exercise and performance. Nutrition. 2004;20(7–8):669–677.
Spriet LL. Exercise and sport performance with low doses of caffeine. Sports Med. 2014;44(Suppl 2):S175–S184.
Shimomura Y, Yamamoto Y, Bajotto G, et al. Nutraceutical effects of branched-chain amino acids on skeletal muscle. J Nutr. 2006;136(2 Suppl):529S–532S.
Blomstrand E. A role for branched-chain amino acids in reducing central fatigue. J Nutr. 2006;136(2 Suppl):544S–547S.
Jeukendrup AE. A step towards personalized sports nutrition: carbohydrate intake during exercise. Sports Med. 2014;44(Suppl 1):S25–S33.
Rowlands DS, Houltham S, Musa-Veloso K, Brown F, Paulionis L, Bailey D. Fructose–glucose composite carbohydrates and gastrointestinal tolerance during endurance exercise. Med Sci Sports Exerc. 2022;54(1):145–154.

Disclaimer:

The content in this blog is for general information only and is not a substitute for professional medical advice, diagnosis, or treatment. Always speak with your doctor or allied health team before changing your diet, exercise, or taking supplements, especially if you have a health condition or take medication. Please use this information as a guide only. Aid Station doesn't take responsibility for individual outcomes.