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During an Ironman, plan familiar carbohydrate-rich food before the start, then take in carbohydrate regularly on the bike and run. Match fluid and sodium to your own tolerance, sweat losses, weather, and race conditions—do not force a fixed drinking volume. Practise the full plan in training and check your event’s current Athlete Information Guide for on-course products.
Build your race-day plan around practiced fuel
An Ironman is too long for race-day nutrition to be improvised. Rehearse what you will eat and drink during long training sessions, including the timing, products, packaging, and quantities you expect to use at race effort. Choose fuel you can carry and consume reliably on the bike and run, and confirm what your specific event supplies rather than assuming every course stocks the same products.
Compare options by carbohydrate per serving and per hour, glucose/fructose composition, ease of use on each leg, gut tolerance, fluid and sodium contribution, and course availability. Gels, drink mix, chews or blocks, and tolerated solid food can all fit a plan; there is no established single best brand or format for every athlete. IRONMAN’s Fuel your body page describes products including Maurten gels and solids and notes regional availability of Precision Fuel & Hydration’s PH 1000. Product availability may vary by event and region.
What to eat before the start
In the days before race day
IRONMAN’s Food and Fluid Guidelines recommend 8–12 g of carbohydrate per kilogram of body weight per day on days three and two before the race, with higher amounts earlier in the loading process. The guide gives 6–10 g/kg daily for the 24–48 hours before the race and advises finishing the last meal or snack early the day before to support tolerance and appetite on race morning. These are the organization’s published guidelines, not amounts every athlete should force; rehearse what works for you.
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- 23g Carbs Per Gel (Training + Race Fuel), Each gel delivers 23g of carbs (91 kcal) to help provide carbohydrate energy during running, cycling, and endurance training.
- Light Texture with Real Fruit Juice, Made with real fruit juice for a smoother, more refreshing gel experience
- Caffeine Free & Vegan Friendly, Clean fueling without caffeine or artificial sweeteners, We believe sports nutrition should fuel your body without tasting artificial
- Pocket Ready 40g Pouches, Easy to carry for training and race day, A mindful choice tested by professionals and enjoyed by all levels of endurance athletes
- TRUSTED SINCE 1994: Founded by British triathletes, HIGH5 has over 30 years of sports nutrition experience, with pocket-ready 40g sachets built for race day.
Race morning
IRONMAN recommends starting to fuel 3.5–4 hours before the start and aiming for 3–4 g/kg of carbohydrate. It also gives 2 g/kg, or amounts as tolerated, two hours before the start. Use familiar foods and spread fluid intake over time instead of drinking a large volume at once. Practise the timing and food choices during training rather than trying them for the first time on race day.
How much carbohydrate to take in during the race
For exercise lasting more than three hours, IRONMAN’s general guideline is 60–70 g of carbohydrate per hour; it says some athletes may tolerate up to 90 g/h. The upper figure is not a universal target. Start with an amount your gut tolerates and practise the schedule in long sessions. The guide recommends a mix of glucose and fructose for maximal absorption and advises testing products such as sports drink, gels, and blocks in training.
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- BERRY FLAVOR GELS: The next evolution of energy gels perfectly proportioned to deliver exactly what you need and nothing you don’t. Formulated with a thin consistency (not paste-like) our high-performance Never2 gel packs are easy to consume with/without water, providing 30g of fast-absorbing energy, and 200 mg of sodium to deliver and retain fluid with a mild berry flavor to reduce the opportunity for gastric distress. Our C30 Energy Gel packs contain 12 single on-the-go servings.
- ELITE PERFORMANCE: Our C30 Energy Gels for everyday athletes are lightly flavored, without any artificial flavors, colors, or unnecessary ingredients. With electrolytes to replace what is lost in sweat, sodium to facilitate rapid water absorption/rehydration, and a 2:1 glucose-to-fructose carbohydrate ratio that provides fast-absorbing optimized fuel delivery. Ideal for endurance running, ultramarathons, long-distance swimming, cross-country skiing, and ultra trail races.
- OPTIMAL FUEL + FLUID: Neversecond products are athlete-focused and designed to accommodate an eating and hydration strategy that will fuel you adequately all the way to the finish line. Consume 1-3 gels every 60 minutes of intense exercise dependent on your needs to deliver optimal fuel and hydration.
- C-SERIES FUEL: Neversecond’s C-Series fueling products are formulated to work together as a system, proven to fuel great performance. Our C-Series fuel products are formulated using 30g increments of carbohydrate which allows you to easily plan, evaluate, and perfect your performance nutrition. Simply mix and match any C-Series products to meet your daily intake requirement.
- NEVERSECOND I Est 2021: Founded by competitive endurance athletes, we help passionate athletes unlock their potential through optimized nutrition, making science-driven products that help athletes optimize performance and exceed their goals. Science First. Neversecond.
Use whichever familiar formats make the plan manageable. On the bike, consider whether you can carry and open each product; on the run, account for what is comfortable to carry and consume while moving. If you expect to use on-course fuel, verify the products in your event’s current Athlete Information Guide. IRONMAN posts its Competition Rules and event guide notice, but course nutrition should be checked for the specific race.
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What to drink on race day
There is no single fluid volume that suits every Ironman athlete. Sweat rate, starting hydration, sweat sodium, gastric emptying, effort, and weather all affect what an athlete can tolerate and needs. USA Triathlon’s race-day fueling guidance emphasizes individual differences and the value of experimenting during training.
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- COLA FLAVOR + CAFFEINE: The next evolution of caffeinated energy gels perfectly proportioned to deliver exactly what you need and nothing you don’t. Formulated with a thin consistency (not paste-like) our high-performance Never2 gel packs are easy to consume with or without water, providing 30g of fast-absorbing energy, 75mg of caffeine for alertness and concentration, and 200mg of sodium for fluid delivery with a mild cola flavor. Our C30 + Energy Gel packs contain 12 single on-the-go servings.
- ELITE PERFORMANCE: Our C30+ Energy Gels with caffeine for everyday athletes are lightly flavored, without any artificial flavors, colors, or unnecessary ingredients. Caffeinated energy gels with electrolytes to replace what is lost in sweat, sodium to facilitate rapid fluid delivery, and a 2:1 glucose-to-fructose carbohydrate ratio to provide fast-absorbing optimized fuel delivery. Ideal for endurance running, ultramarathons, long-distance swimming, cross-country skiing, and ultra trail races.
- OPTIMAL FUEL + FLUID: Neversecond products are athlete-focused and designed to accommodate an eating, hydration, and energy strategy that will fuel you adequately all the way to the finish line. Recommended consumption is 1 caffeinated gel every 60 minutes of intense exercise (maximum 4 caffeinated gels per day) depending on your anticipated completion time.
- C-SERIES FUEL: Neversecond’s C-Series fueling products are formulated to work together as a system, proven to fuel great performance. Our C-Series fuel products are formulated using 30g increments of carbohydrates which allows you to easily plan, evaluate, and perfect your performance nutrition. Simply mix and match any C-Series products to meet your daily intake requirement.
- NEVERSECOND I Est 2021: Founded by competitive endurance athletes, we help passionate athletes unlock their potential through optimized nutrition, making science-driven products that help athletes optimize performance and exceed their goals. Science First. Neversecond.
IRONMAN’s general guide says maximum fluid absorption is usually 1–1.2 L per hour, but that is not an instruction to drink that much. Do not force fluid to meet a number. ACSM’s 2026 exercise-associated hyponatremia Q&A identifies overdrinking as the main risk factor and says drinking to thirst is reasonable for recreational endurance participants.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.How to think about sodium
IRONMAN gives 500–700 mg sodium per litre as a guideline and up to 1,000 mg/L for salty sweaters, while explicitly noting that intake needs customization. These are concentration guidelines, not a reason to increase fluid intake. Extra sodium does not make excessive drinking safe. Athletes with a history of medical problems or unusual fluid needs should seek individualized advice from a qualified professional.
Quick Recap
Best Value
- FRUIT PUNCH FLAVOR GELS: The next evolution of energy gels is perfectly proportioned to deliver exactly what you need and nothing you don’t. Formulated with a thin consistency (not paste-like) our high-performance Never2 gel packs are easy to consume with/without water, providing 30g of fast-absorbing energy, and 200 mg of sodium to deliver and retain fluid with a mild fruit punch flavor to reduce the potential for gastric distress. Our C30 Energy Gel packs contain 12 single on-the-go servings.
- ELITE PERFORMANCE: Our C30 Energy Gels for everyday athletes are lightly flavored, without any artificial flavors, colors, or unnecessary ingredients. With electrolytes to replace what is lost in sweat, sodium to facilitate rapid water absorption/rehydration, and a 2:1 glucose-to-fructose carbohydrate ratio that provides fast-absorbing optimized fuel delivery. Ideal for endurance running, ultramarathons, long-distance swimming, cross-country skiing, and ultra trail races.
- OPTIMAL FUEL + FLUID: Neversecond products are athlete-focused and designed to accommodate an eating and hydration strategy that will fuel you adequately all the way to the finish line. Consume 1-3 gels every 60 minutes of intense exercise dependent on your needs to deliver optimal fuel and hydration.
- C-SERIES FUEL: Neversecond’s C-Series fueling products are formulated to work together as a system, proven to fuel great performance. Our C-Series fuel products are formulated using 30g increments of carbohydrate which allows you to easily plan, evaluate, and perfect your performance nutrition. Simply mix and match any C-Series products to meet your daily intake requirement.
- NEVERSECOND I Est 2021: Founded by competitive endurance athletes, we help passionate athletes unlock their potential through optimized nutrition, making science-driven products that help athletes optimize performance and exceed their goals. Science First. Neversecond.
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- 100% ALL-NATURAL SPORTS NUTRITION – Fruit Puree. Powdered Chia Seeds. Brown Rice Syrup. You don't need a PhD to pronounce the ingredients in Hüma products. Gluten Free, Dairy Free, Vegan Friendly. Huma is the best running gel, cycling gel, or triathlon gel on the market.
- HAPPY STOMACHS – Give your stomach REAL FOOD it can easily process and watch your stomach problems disappear. Kiss dextrose and maltodextrin goodbye.
- THEY ACTUALLY TASTE GOOD – Huma energy gels are the BEST-TASTING energy gels on the market. Made with fruit and natural sources of healthy carbs and protein.
- ACHIEVE YOUR BEST PERFORMANCE, NATURALLY – Huma Gel is made with finely milled Chia Seeds to help modulate an even energy output, and has a 2:1 ratio of short & long chain Glucose to Fructose for maximum carbohydrate uptake.
- PRE & DURING RACE ENERGY – No-Caffeine Gels: Strawberries, Apples & Cinnamon, Blueberries, Mangoes; Caffeine Gels: Chocolate (25mg), Mocha Doubleshot (100mg; Not included), Raspberries (25mg), and Lemonade (25mg). Only 6-7 of the 8 flavors are included in the Variety 12-pack, based on availability.
Check the plan against your event and your own needs
- Rehearse your full eating and drinking schedule in long training sessions, using the products and formats you expect to use on race day.
- Verify on-course nutrition in the specific event’s current Athlete Information Guide; products and availability can vary by race and region.
- Adjust your approach to conditions and tolerance rather than treating general carbohydrate, fluid, or sodium figures as a personal prescription.
- Seek qualified individualized advice if medical history or unusual fluid needs make general guidance unsuitable.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
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