Nutrition & Fueling Guides - Trailia

Science-backed nutrition strategies and fueling plans for trail runners: carbs per hour, hydration, gut training and race-day eating.

18 guides. Each one is available as Markdown by appending .md to its URL.

• Gut Training for Ultra Runners: How to Stop GI Distress on Race Day (10 min read) GI distress causes more ultra DNFs than injury. Here's the research-backed gut training protocol to fix it before race day.
• How Much Water Do You Need? Trail Running Hydration Guide (8 min read) How much water do you actually need on the trails? A practical trail running hydration guide with hourly targets, sodium ranges, and carrying math.
• Sweat Rate Testing: Calculate Your Hydration Needs as a Runner (7 min read) Sweat rate testing takes one run and a bathroom scale. Learn the exact protocol, the formula, and how to turn your number into a race hydration plan.
• RED-S in Runners: Warning Signs and How to Fuel Properly (7 min read) RED-S in runners hides behind stress fractures, missing periods, and stalled performance. Learn the warning signs, the energy availability math, and the fix.
• Vegan and Plant-Based Fueling for Trail Runners: A Guide (7 min read) Vegan trail running nutrition done properly: protein targets and leucine, the four supplements that matter, and how to solve the fibre problem before a race.
• Real Food vs Gels: Build an Ultra Fueling Plan That Works (7 min read) Real food vs gels is the wrong question. Here is when each format works, the carbohydrate targets by race duration, and how to train your gut for both.
• Caffeine Strategy for Ultra Races: Timing, Dosage, Tolerance (8 min read) How to ration caffeine across an ultra race: evidence-based doses, overnight timing for 100 milers, and a tolerance taper that sharpens the response.
• Post-Race Recovery Nutrition: What to Eat in the First 48 Hours (7 min read) Recovery nutrition after an ultra, hour by hour: what to eat when your stomach has quit, how much protein and carbohydrate, and the mistakes that cost a week.
• Real Food vs Gels: Fueling Strategy for 50+ Mile Trail Races (9 min read) Why gels excel early in a 50-mile race, why real food takes over late, and how to build the switch into your race-day fueling plan.
• Fat Adaptation for Ultra Runners: What the FASTER Study and Burke's Research Show (9 min read) The FASTER study found record fat burning in keto-adapted ultra runners; Burke's trials found slower race walkers. What both mean, and how to train low safely.
• High-Carb Fueling for Trail Running: The Science Behind the Revolution (10 min read) High-carb fueling isn't just for elites. Here's what the research says about carbohydrate targets for trail runners and how to build gut tolerance.
• Electrolyte Balance on Long Runs: Sodium, Potassium, and Cramping (9 min read) The science of electrolyte balance on long runs is more complicated than "take more salt." Here's what the research actually says about sodium, potassium, and cramping.
• Race Day Nutrition Strategy for Mountain Ultras (10 min read) Fueling a mountain ultramarathon is nothing like a road race. Here's the science-backed strategy that keeps you moving when everything hurts.
• What to Eat Before a Trail Race: Race Day Nutrition Timing Guide (10 min read) Your pre-race nutrition can make or break your trail running performance. Learn exactly what to eat, when to eat it, and what to avoid in the 72 hours before race day.
• Calories per Hour in Ultra Trail Running: How to Calculate Your Needs (10 min read) Where the 1 kcal per kg per km rule comes from, how climbing, heat and altitude change it, and how to turn your hourly burn into a fueling plan you can stomach.
• Carb Loading for Trail Races: Timing and Strategy Guide (9 min read) Master carb loading for trail races with evidence-based timing protocols, portion strategies, and race-day fueling plans for peak performance.
• How to Manage Nutrition for Your First Trail Running Race (9 min read) Master race day nutrition with this science-backed guide. Learn fueling strategies, hydration protocols, and common mistakes to avoid in your first trail race.
• Trail Running Nutrition: Complete Fueling Guide for Long Runs (7 min read) Master trail running nutrition with our science-backed fueling guide. Learn optimal carbohydrate intake, hydration strategies, and how to prevent GI issues on long runs.

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