Mastering Marathon Fueling: Time vs Distance

Should you fuel based on time or distance?

Running a marathon is no joke. It’s a huge physical and mental challenge, and how you fuel along the way can make all the difference between a strong finish or hitting the dreaded “wall.”

Whether you’re gearing up for your first marathon or chasing a PR, getting your fueling right is crucial. But here’s the big question: Should you fuel based on time (every 30 minutes or so) or distance (every 5 miles)? Let’s break it down in a way that makes sense for you and your race day goals:

Why Fueling is So Important

Your body only has so much energy stored up in the form of glycogen—this is the stuff your muscles burn through as you run. Unfortunately, you only have about 90-120 minutes of glycogen before things start going south. Ever heard of “hitting the wall”? That’s when your body runs out of glycogen, and suddenly everything feels *a lot* harder. Trust me, it’s not fun. The good news is you can prevent this with proper fueling—taking in carbs like gels, sports drinks, or energy chews during your race to keep your energy levels steady.

Fueling by Time

One popular way to fuel during a marathon is by sticking to time-based intervals. For example, you might take a gel every 30-45 minutes. The idea here is to stay ahead of your body’s energy needs instead of waiting until you feel tired or sluggish.

Why It Works:

1. Consistency is key: It’s easy to forget to fuel when you’re in the zone, but a set schedule helps prevent that.
2. It’s pace-proof: Whether you’re speeding along or taking it a bit slower, time-based fueling ensures you get the energy when you need it.
3. No surprises: Fueling regularly keeps your energy steady, so you won’t hit a low point unexpectedly.

How to Do It:

• If you’re faster (sub-4-hour finish): Try fueling every 30-35 minutes. Your pace is quicker, so you’ll need to refuel more frequently to keep up.
• Mid-pack runners (4-5 hours): Every 35-40 minutes should do the trick. You’re out on the course longer, but you’re also burning energy a bit slower.
• Sexy pacers (5+ hours): Every 40-45 minutes. Your pace is more relaxed, so your energy needs are a bit more spread out.

Fueling by Distance

Some runners prefer to fuel based on the miles they’ve covered. For example, you might decide to take in carbs every 5 miles. This method works well if you like to break your race into segments or if it just feels more natural to you.

Why It Works:

1. Mental checkpoints: Knowing you’ll fuel at certain mile markers can give you something to look forward to. It’s like giving yourself a mini reward!
2. Course planning: You can align your fueling with aid stations or tougher sections of the race.
3. Training-friendly: If you’ve been training by mileage, it makes sense to keep that rhythm on race day.

How to Do It:

• Faster runners: Fuel every 4-5 miles. You’re moving at a quicker pace, so refueling regularly is key to keeping up your energy.
• Mid-pack runners: Every 5-6 miles is usually a good bet. You’re covering ground at a moderate pace, so your fueling needs are spaced out a bit more.
• Sexy pacers: Every 6-7 miles works well. You’ll still need the energy, but your body isn’t burning through it as fast.

Time vs Distance: Which One is Right for You?

The truth is, both methods work, you just have to figure out which one fits you best.

Things to Consider:

1. Your pace: If you’re a faster runner, fueling by time can work well since you’re covering miles quickly. Slower runners may benefit more from distance-based fueling because their energy needs are stretched over a longer period.
2. The race course: If the course has tough hills or unpredictable weather, you might need to fuel more often in certain spots. Flexibility is key!
3. Your training: How you’ve fueled during long training runs should guide your race day plan. Stick with what your body is used to—no surprises!

Why Not Both? The Hybrid Approach

A lot of runners actually use a mix of both time and distance fueling. For example, you could plan to take a gel every 5 miles but also sip on sports drinks every 20 minutes. This combo approach gives you flexibility and helps you adjust as the race unfolds. Sometimes, your body will ask for a little extra fuel, and sometimes it’ll be cruising along just fine!

Practice Makes Perfect

No matter which method you go with, *practice is everything.* Use your long training runs to figure out what works best for you. Test out different gels, drinks, or whatever fuel you’re planning to use, and nail down your strategy before race day. You don’t want to leave it to chance when you’re 18 miles in and needing an energy boost!

At the end of the day, fueling is about finding what keeps you feeling strong, steady, and ready to tackle those 26.2 miles. Everyone’s body is different, so go with the plan that feels right for you—and remember, you've got this!

Good luck with your marathon, and enjoy every mile!

Fuel smart, run happy, and finish strong 💪