How to Prepare for a Full Marathon: A Practical Guide
Preparing properly for a marathon can be the difference between crossing the finish line strong or struggling to get there at all. Whether you're attempting your first 42.2K or looking to improve your time, this guide covers everything you need to train better, avoid common mistakes and feel more confident on race day.
From gear and pacing to fueling, injury prevention, and heart rate zone training, this article shares many tips and tricks that I’ve learned over the years to help you finish your race.
By Quentin van Bentum • July 2025
Essential Gear Checklist for Marathon Training
Marathon clothing for all conditions: The right clothing can really affect your long runs. During training, test gear in various weather conditions so you know what works. Avoid wearing anything new on race day—get comfortable with your outfit first.
Choosing the right running shoes: Your marathon shoes should fit comfortable and be broken in before race day. A quality pair of running shoes typically lasts 600–700 km. Some runners opt for carbon plate shoes for race day, but they're not essential for everyone. If you do consider them, make sure to research thoroughly.
My go-to trainers are the Puma Velocity Nitro 3. I am on my fourth pair now and they have been extremely durable, versatile and kept me injury-free.
Running socks and underwear to prevent chafing: Chafing and blisters can ruin your race. Invest in moisture-wicking, seamless running socks and supportive, anti-chafe underwear. These small upgrades can make a huge difference in comfort.
Hydration belt or running vest: Even though most marathons provide water stations, carrying your own water and energy gels during training runs is essential. A running belt or vest makes hydration and fueling easy and hands-free.
Running watches: Having a running watch can make training easier to track and improve. It helps you monitor pace, distance, heart rate, and splits without needing your phone.
Avoiding running Injuries
Staying healthy during marathon is as important as running the marathon itself. The tips below will help you reduce the risk of injury and keep your body strong through every phase of your training.
- Running technique: Doing proper research or getting in contact with an in person coach can help your running technique and prevent many injuries.
- Cadence: A higher step rate reduces the impact of each step. There is no standard for each individual. A common guideline is 180 steps per minute, but everyone has their natural cadence range, so don’t get too stuck on this.
- Listen to your body: Recovery is just as important as training. If lingering pains start arising all the time, it might be time to take it easy for a bit.
- Progress gradually: Increase volume and intensity step by step.
- Consistency wins: Showing up consistently beats occasional hard efforts.
- Follow a running plan: A structured and personalized marathon plan helps you train smarter, safer, and more efficiently. If you want a free personalized training plan, check out my Running Plan Generator here and get a running plan that fits your goals!
Example of a Personalized Running Plan
Here's a visual example of what the first 4 weeks of a personalized marathon running plan looks like using my free tool. Every plan is based on your goal, schedule, and current fitness level. You can generate one in seconds with the link below.
Understanding Heart Rate Zones
Training by heart rate helps ensure you're working at the right intensity during your workouts.
- Zone 1: Very easy pace – mainly for recovery runs.
- Zone 2: Easy pace – for easy, long, and recovery runs.
- Zone 3: Moderate intensity – used for tempo and race pace work.
- Zone 4: Threshold work – short efforts at a hard but sustainable pace.
- Zone 5: Max effort – used occasionally for VO₂ max work or short intervals.
Heart rate zones can vary widely between individuals and shouldn’t be the only metric you train by. But having a basic understanding of how they work can help you train more efficiently. If you're unsure of your personal zones, try using my Heart Rate Zone Calculator to get started.
Weekly Mileage
While interval and tempo runs are important, your total weekly mileage plays in many cases a bigger role in marathon success. Gradually building and maintaining a solid weekly volume helps develop endurance, efficiency, and resilience over time. If you're feeling fatigued or on the edge of burnout, it’s often smarter to swap hard sessions for easy runs, allowing you to hit your mileage target without overstraining your body.
Stretching and warming up
Stretching and warming up properly before each run prepares your body for effort and helps prevent common running injuries. Post-run stretching is just as important, it supports recovery, reduces stiffness, and keeps your body moving well, especially after harder sessions.
- Pre-run: Try a 5-minute dynamic warm-up to activate your muscles and get your heart rate up.
- Post-run: Especially important after long runs, pace workouts, or intervals. Try one of the following stretching routines:
Fueling & Hydration on Training Days
Proper fueling and hydration strategies will help you get the most out of your training sessions and recover faster. What you eat and drink before, during, and after your runs has a big impact on how you feel, perform, and adapt to the training load.
- Pre-run fuel: Always eat something. For short runs, fruit or a carb snack is fine. For longer runs, eat a carb-rich meal at least an hour before.
- During long runs: Consider using energy gels. Your body has enough glycogen stored for around 1.5–2 hours of sustained effort (depending on pace). To be safe, take gels on any run longer than 1.5 hours. Aim for at least 60 grams of carbs per hour. If you want to make your own energy gels, you can find a recipe Here
- Hydration: Always drink before you run. For runs over 10–12 km, carry water, especially on warm days.
Make Your Own Energy Gels
Curious about what goes into a homemade energy gel? Here’s a peek at the ingredients I personally use. It’s simple, affordable, and easy to tweak to your taste. Check out the full DIY recipe Here
Fueling & Hydration before and During Your marathon
Race day fueling can make or break your performance. You’ve trained for weeks — now it’s about managing your energy, hydration, and gut comfort to make sure you reach the finish line feeling strong.
- Carbohydrates: Your main fuel source. Without them, you’ll crash.
- Carb loading: Start 2–3 days before race day. Aim for 8–12g of carbs per kg of body weight per day. This will help you sustain more energy throughout the race!
- Race morning: Wake up early and eat a light, carb-rich meal about 1–2 hours before the start. (Practice this in training to avoid surprises)
- Energy gels: Plan for 2–3 per hour, aiming for 80–90g of carbs per hour. This is slightly higher than during training due to race intensity.
- Caffeine (optional): Many runners benefit from it. Test it during training — don’t try it for the first time on race day. Tip: 200 mg 30 minutes before the race, and possibly another 100 mg after ~2 hours. I like to take enegey chews like these,
- Water: Stay hydrated. Use every water station, even if it’s just a few sips. Staying hydrated is extremely important during races.
- Electrolytes (optional): In hot conditions, bring electrolytes to help prevent cramping and dehydration.
Marathon Race Strategy
Having a solid race strategy can be the difference between a breakthrough performance and a painful blow-up. Stick to a plan that suits your training and energy levels, and run smart from start to finish.
- Use pacers: If your race offers official pacers, consider running with them. They help you maintain a consistent pace without obsessively checking your watch.
- Try a negative split: Start slightly slower than your target pace, then gradually speed up and finish strong. It’s a proven strategy to avoid burnout.
- Don’t go out too fast: Early-race excitement can lead to poor pacing and energy crashes later on. Stay controlled in the first few kilometers.
Common Mistakes to Avoid
Even experienced runners fall into these traps. Avoiding the most common training mistakes will help you stay healthy, progress consistently, and enjoy the process.
- Ignoring your body: Don’t follow your plan blindly. If you're tired or in pain, adjust your training.
- Running too hard too often: Not every session should feel intense. Easy runs should be truly easy to allow recovery and adaptation.
- Skipping recovery: Rest days and easy runs are critical for progress. Skipping them increases injury risk and slows improvement.
- Inconsistent mileage: Big spikes or dips in weekly volume can lead to burnout or injury. Aim for gradual, consistent progression.
- Being too rigid: Life happens. Be flexible when needed, but stay committed overall.
Final Note
Marathon day is the celebration of all your hard work. Whatever the clock says at the finish line, the effort, discipline, and dedication it took to get there matter most.
- Finishing a marathon is a huge accomplishment: Regardless of your time.
- Don’t chase validation through numbers alone: Meaning comes from the journey, not just the goal.
- Trust your preparation: Run smart, listen to your body, and stay present in the moment.
- There’s always another race: Use every experience as a stepping stone for the next one.
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