Nutrition & Fueling
Hyper-fueling protocols, gut training, sodium, caffeine, race-week loading.
20 articles · sorted by most recent
120g Carbs Per Hour in a Marathon: What the 2.6% Study Really Shows
A 2025 lab study found running cost 2.6% less oxygen at 120 g/h than at 60 g/h. It tested 8 elite men and never measured race time. Here's what it means for you.
Marathon Fuelling Plan: How Many Grams of Carbs per Hour, and How to Train Your Gut
Most marathoners eat about 35 g of carbs an hour. Runners who ate 60 g/h finished about 11 minutes faster, and two weeks of gut training cut stomach symptoms by about 60%.
70.3 Race-Day Nutrition: A Simple Hour-by-Hour Fuelling Plan
Eat 60 to 90 g of carbs per hour on the bike, starting in the first 15 minutes. The average 70.3 athlete takes in only 65 g/h, and many sit well below 60.
Probiotics for Endurance Athletes: The 4-Week Rule Most Race-Week Habits Miss
Probiotics cut GI and cold symptom severity in trials, but only at a specific dose with a 28-day lead-in. Starting race week gets you none of the documented benefit.
Omega-3 for Endurance Athletes: What a 2026 Meta-Analysis Says About the Dose That Actually Cuts Inflammation
A standard 1000mg fish oil softgel delivers ~300mg EPA+DHA, about 15% of the ~2,000mg/day dose linked to lower IL-6, CK, and muscle soreness in pooled trial data.
Fueling a 200-Mile Gravel Race: The Aid-Station Math and Solid-to-Liquid Switch That Keeps You Eating at Hour 12
Lab ceilings say 90-120 g/h of carbs; real ultra-event field data shows riders average 46.7 g/h. Unbound's 78-mile checkpoint gap forces you to carry the difference yourself.
Caffeine Mouth Rinse: Does Swishing and Spitting Actually Work?
One meta-analysis finds a real but small benefit (g=0.12). A second, smaller one finds nothing (p=0.09). Here's what a 5-second caffeine rinse actually does in the 60 minutes it's been tested.
Plant-Based Endurance Athletes: What the 2024 Meta-Analyses Say About Protein Timing and Iron
Plant-based athletes perform fine but need bigger per-meal protein doses to trigger muscle repair. Iron is the real risk: 1.8x higher needs and a 36% absorption dip after hard workouts.
Heat-Induced GI Distress: The Blood-Flow Mechanism Behind Race-Day Stomach Trouble
Heat, not your gels, usually causes race-day stomach trouble. Gut blood flow can drop 80%, and permeability spikes above 38.5°C core temperature. Here's the fueling fix that actually targets it.
GLP-1 Drugs and Endurance Training: What Ozempic and Zepbound Do to Muscle, Fueling, and Performance
GLP-1 drugs like Ozempic and Zepbound can strip 25-40% of weight loss from muscle. Here's the protein target, RED-S risk, and fueling fix for endurance athletes.
Caffeine Before a Race: Why Your CYP1A2 Genotype Decides Whether It Helps or Hurts
Same 4 mg/kg caffeine dose, opposite outcome: CYP1A2 AA athletes ran 6.8% faster, CC athletes ran 13.7% slower in a 10K time trial. One gene decides which one you are.
How Long Does Gut Training Take to Work? The 2-Week Protocol, Explained
Two weeks of daily carbohydrate practice cuts breath hydrogen by up to 54% and GI symptoms by up to 63%, using the exact dose from the research.
How Much Protein Per Meal Do Endurance Athletes Need? The 2025 Meta-Analysis Answer
Endurance athletes need about 0.25 g/kg protein per meal (19-24g) and roughly 0.5 g/kg (33-48g) right after hard sessions, per a 2025 meta-analysis of 75 trials.
Programmed vs. Thirst-Driven Hydration in Ultras — What a 2025 Narrative Review Actually Concludes
A 2025 University of Arkansas review of 6 ultra-endurance studies found neither drinking schedule nor thirst alone wins. A sweat-rate floor plus thirst ceiling is the evidence-based answer.
Train Low, Compete High: The Carbohydrate Periodization Strategy That Actually Improves Endurance Adaptation
Train low, compete high works — but only on specific session types. The Marquet sleep-low protocol improved 10-km run time 2.9% with zero change in total carb intake.
Energy Availability: Why Under-Fueling Makes Endurance Athletes Slow
Under-fueling to get lean makes you slower, not lighter. Energy availability below 30 kcal/kg FFM/day cuts swim speed by 9.8% in 12 weeks and costs athletes 22+ training days a year.
Carbohydrate Loading Before a Marathon: The 3-Day Protocol That Actually Works
One pasta dinner does almost nothing. A real carbohydrate loading protocol runs 3 days at 8–12 g/kg/day and can push your glycogen stores 84% above baseline.
Gut Training to 120 g/hr: The Real Mechanism Isn't Glycogen Sparing
Training your gut to absorb 120 g/hr cuts muscle damage markers by 67% — not because it spares glycogen, but because it prevents breakdown. Here's the 4-week protocol.
Sodium Bicarbonate for Endurance: The 1–3% Performance Hack (and the Sodium Math Nobody Mentions)
Sodium bicarbonate improves performance by 1.7% across 38 studies — but a standard 0.3 g/kg dose delivers ~5,700 mg of sodium, more than twice the US daily reference intake.
Sodium for Heavy Sweaters: How to Calculate Your Real Replacement Need
Generic 300–600 mg/hr sodium guidelines fail the top 20–30% of sweaters. A 10x range in sweat sodium concentration means two athletes in the same race can need 4x different amounts.