Fueling Your Ultra: A 6-Month Nutrition Plan for Ultramarathon Training

Suppose you've registered for an ultramarathon six months from now. You've got your training plan dialed in. But here's the truth that catches most first-time ultra runners off guard: you can't out-train bad nutrition.

Whether you're preparing for the Sparks Backyard Ultra or the Biggest Little Ultra, what you eat in the months leading up to race day matters just as much as the miles you log. Let's break down some items to add to your diet, what to remove, and how to fuel your body for the challenge ahead.

The Foundation: Why Nutrition Matters More for Ultras

Traditional marathon training focuses heavily on mileage. Ultra training? It's about teaching your body to become a fat-burning machine that can sustain effort for hours, and sometimes through the night.

Your nutrition strategy over the next six months will:

• Build the metabolic flexibility to burn both carbs and fat efficiently

• Strengthen your immune system to handle training stress

• Reduce inflammation to speed recovery

• Train your gut to process food while moving

• Maintain energy levels through increasingly long training sessions

Think of these six months as gut training, metabolic training, and fueling practice all rolled into one.

What to ADD to Your Diet

Complex Carbohydrates (The Right Kind)

Your body needs carbs, but the quality matters. Add more:

• Sweet potatoes and regular potatoes

• Oatmeal and overnight oats

• Quinoa and brown rice

• Whole grain bread and pasta

• Fruits, especially bananas, berries, and dates

These provide sustained energy without the crash. Unlike simple sugars, complex carbs keep your blood sugar stable during long training sessions.

Healthy Fats (Your Secret Weapon)

Training your body to burn fat is crucial for ultras. Incorporate:

• Avocados (nature's perfect recovery food)

• Nuts and nut butters (almonds, cashews, peanut butter)

• Seeds (chia, flax, pumpkin)

• Olive oil and coconut oil

• Fatty fish like salmon and mackerel

Start adding these to every meal. They're calorie-dense, which you'll need as your training volume increases, and they teach your body to access fat stores during long efforts.

Quality Protein

Recovery happens when you're resting, and protein is the building block. Focus on:

• Lean meats (chicken, turkey, lean beef)

• Fish and seafood

• Eggs (one of the most bioavailable protein sources)

• Greek yogurt and cottage cheese

• Legumes and beans

• Protein powder (whey or plant-based) for convenience

Aim for protein at every meal, not just dinner. Your muscles are recovering 24/7 during heavy training.

Anti-Inflammatory Foods

Ultra training creates inflammation. Combat it with:

• Leafy greens (spinach, kale, arugula)

• Colorful vegetables (bell peppers, beets, carrots)

• Berries (blueberries are particularly powerful)

• Turmeric and ginger

• Green tea

These foods help your body recover faster and reduce the risk of overtraining injuries.

Electrolytes and Minerals

As your training volume increases, you'll need more than just water. Add:

• Bananas (potassium)

• Dark leafy greens (magnesium)

• Nuts and seeds (magnesium and zinc)

• Sea salt (sodium—yes, you actually need this)

• Coconut water (natural electrolytes)

Don't wait until race day to think about electrolytes. Your body needs them daily during heavy training.

What to REMOVE (or Significantly Reduce)

Processed Foods and Added Sugars

These provide empty calories and energy crashes. Minimize:

• Candy and sweets (except as intentional race fuel)

• Soda and sugary drinks

• Packaged snacks with long ingredient lists

• Fast food

• Highly processed breakfast cereals

Exception: During actual long training runs, quick-burning sugars (gels, chews, sports drinks) are useful. We're talking about your everyday diet here.

Excessive Alcohol

A beer after a long run might be tempting, but alcohol:

• Impairs recovery

• Disrupts sleep quality (when your body does its repair work)

• Dehydrates you

• Reduces protein synthesis

You don't have to quit completely, but save it for special occasions during heavy training blocks.

Foods That Cause Inflammation

These slow recovery and increase injury risk:

• Fried foods

• Excessive red meat (once or twice a week is fine)

• Refined grains (white bread, white pasta)

• Trans fats and hydrogenated oils

• Excessive dairy (if you notice it causes inflammation for you)

Pay attention to how your body responds. Some people handle dairy fine; others feel better without it.

Heavy, Hard-to-Digest Foods Before Training

Don't eat these within a few hours of running:

• High-fiber foods right before runs (save these for other times)

• Large amounts of fat before running

• Spicy foods (unless you've tested them thoroughly)

• New foods on long run days

Test everything during training, never on race day.

The 6-Month Timeline: When to Make Changes

Months 1-2: Build Your Foundation

Focus on adding whole foods and removing the obvious junk. Don't overhaul everything at once. Make sustainable changes you can maintain.

Months 3-4: Start Race Fuel Testing

Begin experimenting with what you'll eat during the actual race:

• Test different gels, chews, and bars on long runs

• Practice eating real food while moving (sandwiches, boiled potatoes, pretzels)

• Figure out your hydration strategy

• Pay attention to what settles well and what doesn't

Your stomach needs training just like your legs. Some runners can eat pizza during an ultra. Others can only handle simple carbs. Find out what works for YOU.

Months 5-6: Fine-Tune and Practice

By now, you should know:

• What pre-run breakfast works best for you

• Which race fuels your stomach tolerates

• How much and how often you need to eat during long efforts

• Your hydration needs per hour

Practice your exact race-day nutrition plan during your longest training runs.

Race Fuel vs. Training Fuel: Understanding the Difference

Training Fuel (90% of the time): Whole, nutrient-dense foods that support recovery, reduce inflammation, and build metabolic flexibility. This is about long-term health and adaptation.

Race Fuel (during long efforts): Quick-digesting carbs that provide immediate energy. Gels, chews, simple sugars, and easily digestible foods. This is about performance in the moment.

Don't confuse the two. Eating like you're racing all the time will leave you inflamed and run down. But trying to fuel a 6-hour training run with only whole foods might leave you bonking.

Hydration: The Often-Overlooked Element

Proper hydration starts days before your long runs, not the morning of. During these six months:

• Drink consistently throughout the day (not just during runs)

• Monitor urine color (pale yellow is the goal)

• Add electrolytes to water for runs over 90 minutes

• Practice your race-day hydration strategy on every long run

• Don't wait until you're thirsty, by then you're already dehydrated

A good rule of thumb: drink 16-20 ounces of water with electrolytes for every hour of running.

Listen to Your Body

Here's the most important advice: your body will tell you what's working. During these six months, pay attention to:

• Energy levels throughout the day

• Recovery time between hard efforts

• Sleep quality

• Digestive issues

• Mood and mental clarity

• Performance improvements (or lack thereof)

If something isn't working, adjust. Nutrition is highly individual. What works for your training partner might not work for you.

The Bottom Line

Ultra training demands more from your body than almost any other athletic pursuit. You're asking it to perform for hours on end, often through fatigue, discomfort, and mental challenges. One thing you can easily do is fuel it properly.

Over the next six months, focus on whole foods, adequate protein and healthy fats, plenty of vegetables, and strategic carbohydrates. Remove the processed junk that's holding you back. Test your race-day nutrition religiously during training.

Your body will adapt. Your gut will strengthen. Your energy systems will become more efficient.

Ready to fuel your ultra journey? Register for the Sparks Backyard Ultra (June 2026) or Biggest Little Ultra (October 2026) at BiggestLittleUltra.com/registration

Need more training guidance? Check out our Complete Beginner's Training Guide