How to choose and use race day energy gels and chews to minimize stomach upset while maximizing energy delivery
On race day, selecting the right gels and chews matters as much as pace, shaping how well you sustain effort, prevent GI distress, and finish strong through strategic timing, flavor variety, and hydration balance.
In endurance racing, energy gels and chews are convenient sources of quick calories that help you maintain pace without slowing you down to chew solid foods. The best choices balance carbohydrate type, concentration, osmolarity, and personal tolerance. Start by evaluating ingredients: look for easily digestible carbohydrates, minimal artificial fats, and little or no fiber that can irritate the stomach. Consider caffeine content if you tolerate it well, but avoid surprises by testing it in training rather than on race morning. Assess packaging and texture—gel pouches should flow smoothly, and chews should be easy to swallow without pinching the jaw. Practical trials during long workouts reveal what your stomach can handle at high tempo.
A practical framework for gel and chew selection begins with a steady 60–90 gram per hour carbohydrate target, which many elite athletes replicate in their race plans. Start with a modest mix: one gel plus a few chews each hour, then adapt based on effort, heat, and sweat rate. If you consistently feel heaviness or stomach discomfort, consider reducing concentration by mixing gels with water or choosing a lighter formulation. Hydration also matters; sipping water with gels aids absorption and lessens bolus sensations. Rotate products to prevent intolerance to a single flavor or additive. Finally, establish a simple fueling map for the first six hours of a long race so you don’t scramble under pressure.
Choose a spectrum of flavors and textures for tolerance
Consistency is the foundation of race day fueling. Rather than improvising, create a reliable routine that you practice during training. Set a schedule for gel and chew intake that aligns with miles or minutes rather than vague milestones. This helps your gut anticipate the incoming fuel and reduces spikes in glucose that can crash later. Pay attention to stomach cues: if you notice fullness, gurgling, or reflux, revise your timing or switch to gentler formulations. Carry backup options, including a non-citrus flavor and an alternative carbohydrate source in case of demand. By rehearsing this plan, you transform fueling from a stress trigger into a predictable rhythm.
Temperature, pace, and terrain influence how well gels and chews work. Heat accelerates gastric emptying but can worsen dehydration, changing how quickly fuel reaches your bloodstream. Slower paces during climbs may require different quantities than high-speed sections, so be prepared to adjust rather than rigidly sticking to a single plan. Practice opening, consuming, and washing down products with small sips of water so you never fumble under fatigue. If you feel nauseated, try a lighter texture or switch to plain, dissolved carbohydrates rather than dense chews. Training sessions that simulate race-like conditions build confidence for the actual event.
Build confidence by simulating race fueling during long workouts
Flavor variety helps you maintain interest and tolerability across hours of racing. Some athletes respond better to fruity gels, while others prefer neutral or even salted flavors. Texture consistency matters as well; a thin gel can slide down easily, whereas a thicker chew might require more water. Rotate flavors to reduce sensory adaptation, which can dull perceived energy or trigger stomach distress when flavors become monotonous. Keep a log of how each product feels after different intensities and temperatures. This record will become a practical reference when you plan your race-day lineup, ensuring you avoid flavors that caused issues in prior builds.
In the realm of digestion, the density of carbohydrates matters. High-osmolality gels can draw water into the gut, sometimes producing cramps or diarrhea in sensitive athletes. If you notice these signs, switch to formulas with a lower osmolarity or dilute gels with additional water. Conversely, ultra-dense options may be beneficial for very long sections where steady energy is critical, provided your gut tolerates them. The goal is to optimize gastric emptying without taxing the intestine. Regular training sessions comparing two or three fueling strategies reveal the approach most suited to you, your course, and your gear.
Monitor gut comfort and energy delivery in real time
Simulated race fueling creates a rehearsal that reduces decision fatigue on race day. Practice the exact sequence you intend to use, including the interval between each intake and how much water accompanies it. This drill also helps you gauge cumulative carbohydrate load and how your body handles it as fatigue grows. If you plan to use caffeine, test the timing and dose during workouts to gauge sleep impact and stomach response. Keep your kit organized so you can access products quickly without breaking your rhythm. The more realism you inject into training, the smoother the adaptation becomes.
For double-checking, simulate hot conditions as well. Heat alters gastric emptying and increases dehydration risk, so running shorter simulations in warmer environments can reveal hidden weaknesses in your fueling protocol. Collect feedback from your gut and skin—signs like dry mouth or excessive thirst can indicate hydration gaps. If a plan fails under these conditions, adjust the ratio of fluids to solids, reassess gel density, or swap in lighter chews designed for higher heat endurance. A well-tested routine reduces surprises during peak effort.
Finalize a personalized, flexible fueling playbook
Real-time gut monitoring is a useful skill for all endurance athletes. Learn to notice the onset of cramps, nausea, belching, or pressure behind the sternum, then adapt quickly. If discomfort arises, pause and reassess the types and timing of what you’ve ingested, rather than pushing through. Small adjustments, like consuming smaller amounts more frequently or switching to a liquid form for a stretch, can dramatically change outcomes. Maintaining a steady flow of carbohydrates helps prevent energy troughs that often accompany stomach upset. Your body will thank you for the attentive, flexible approach.
Energy delivery isn’t solely about calories; it’s about consistent availability of glucose to exercising muscles. To maintain stable energy, your plan should avoid long gaps between feedings and minimize post-ingestive spikes. In practice, this means keeping servings within a predictable cadence and favoring products with a balance of glucose and fructose if you tolerate them. Some athletes find maltodextrin-based gels gentler on the gut, while others prefer real fruit chews. The key is personalization through careful trial and careful note-taking, ensuring your race-day energy hits align with your physiologic signals.
The final step is compiling a personalized playbook that remains adaptable. List your approved products, timing schedule, and contingency options, such as alternate flavors or a switch to liquids only during difficult segments. Document hydration targets alongside fueling moments to maintain stomach comfort and electrolyte balance. Your playbook should fit your body size, training load, and the course profile, not a generic template. Rehearse it with daylight clarity during long workouts so you’re ready when adrenaline, heat, and fatigue collide on race day. Confidence grows when you own a system that works for you.
After each race season, review fueling outcomes with honesty. Note which gels and chews delivered energy without discomfort, which triggered mild distress, and where improvements are possible. This reflection informs a refined regimen that evolves with your training status and race goals. Updates might include new product trials, adjusted concentrations, or alternate timing around transitions and aid stations. With disciplined experimentation and careful logging, you create a durable, evergreen fueling strategy that supports peak performance for any distance, any course, and any weather.