How to Fuel for Marathon Training with a Focus on Nutrition

Written by Laoise Bennis ANutr

Preparation Guide

Before diving into the specifics of nutrition, it’s essential to outline a solid training plan. Most half or full marathon training schedules range from 10 to 16 weeks, depending on your current fitness level. Here are the key components to focus on:

1. Build a Strong Running Base

If you’re new to running, spend a few weeks gradually increasing your mileage before starting a structured plan. Aim to run 3–4 times per week, including a long run to build endurance. Focus on minutes run versus miles or kilometres clocked. Training with friends or joining a run club can help keep you motivated. For structured plans, check out this one by Catherina McKiernan & Mick Clohisey for the Dublin Half Marathon.

Remember, the goal with training is to build endurance, and you should be moving at a lower heart rate / slower speed for most of your mileage to reduce the risk of injury or burnout. You can then mix in tempo runs or interval runs to work on your speed (if that is a goal).

2. Incorporate Strength Training

Strength training is a critical component of your preparation. Building strength helps prevent common injuries like shin splints, improve running economy, and enhance overall performance. Focus on exercises like squats, lunges, deadlifts, and core work 1-2 times per week.

Dr. Brian and his team have completed a systematic review that showed the addition of strength training in an endurance athlete’s programme for improved economy, VO2max, muscle power and performance (Beattie et al, 2014). His team have also completed an intervention study that evidenced 40 weeks of strength training can improve VO2 max, running economy and maximal strength without hypertrophy in competitive distance runners (Beattie et al. 2017)

3. Rest and Recovery

People often forget that rest is an essential principle of training. Overtraining can lead to burnout or injury, so listen to your body and schedule rest days. Try to plan a rest day before or after your long run. Active recovery activities like yoga or light stretching can also aid in muscle repair.

4. Get Race Practice

With your first half or full marathon it can be scary navigating the race itself, especially with bigger events that sometimes see tens of thousands of runners. If you’ve never done another race before it can be worth looking for a local 5km/10km/10 mile run. This will help you practice for the actual race.

Nutrition for Marathon Training

Your training plan will only be as effective as the fuel you provide for your body. Nutrition plays a key role in helping you perform at your best, recover faster, and build endurance. Here’s how to optimize your diet:

1. Fuelling Your Body for Endurance

Carbohydrates are your primary energy source during distance running. Aim to include complex carbs like whole grains, sweet potatoes, and legumes in your meals. Pair these with lean proteins and healthy fats to create balanced meals that sustain your energy levels. Check out our blog on carbs pre and post exercise here

Long-Run Nutrition Strategies

Tips to avoid trips to the toilet and fuel well. The long runs are the trickiest to plan for, especially as everybody will respond differently to fuelling so it’s about finding what works best for you by trial and error. You also want to use your long runs as tests for race day so that you don’t try anything new out on race day.

1. Avoid high fibre and high fat foods. Focus on carbohydrates with a little protein too.

Why? – Nausea, gas, bloating and needing the toilet can be caused by feeling full and uncomfortable especially with the motion of running. This is because foods high in fibre and fat take longer to break down. Focus on a pre run meal that is carbohydrate focused, e.g. breakfasts such as oats with honey work well. Protein is good to keep you satiated pre long run, try something light like eggs or scrambled tofu.

2. Hydrate

Why? Being hydrated before you run and using electrolytes and fluids on runs longer than 60 minutes helps hydrate, prevent gastrointestinal distress, and supports performance. Evidence shows 2% or more dehydration has resulted in significant deterioration in mental function which is a big part of performance.

Did you know – Thirst is not an effective indicator of hydration status while exercising. There is usually a significant fluid loss before you feel thirsty. When drinking, your thirst will be satisfied well before these losses have been fully replaced.

3. Practice your pre-run and in-race fuelling strategy

Why? – Nothing New on Race Day. Regular practice helps you identify which foods and gels your stomach can tolerate and which ones to avoid, reducing the risk of GI distress or discomfort.

By gradually introducing the foods or gels you plan to use on race day, you can train your gut to process them more efficiently. With consistent effort, your digestive system will adapt to the demands of digestion during your performance.

If you choose to use gels it can be helpful to consume them slowly over a 5-10 minute period during your run as this can reduce the risk of discomfort.

4. Recovery

Ensure you get a balanced meal with carbohydrates, protein for muscle repair, fruit and veg to recover after your run. A lot of our customers who are runners take a Whole Supp shake post run which is perfectly balanced. Add in some mobility stretching and flexibility too and a good sleep to optimise recovery.

Race Week Nutrition Tips

As race day approaches, stick to foods you have practiced with to avoid any surprises. Carb-load two to three days before the race with easily digestible options like rice, pasta, and bread. Stay hydrated and avoid over-consuming fiber or heavy, rich foods.

Final Thoughts

Preparing for your first half or full marathon is a rewarding experience that combines physical and mental challenges. By following these training tips and prioritising nutrition, you’ll set yourself up for success. Embrace the journey – all the training runs, every meal that fuels you, and the thrill of race day itself. Running success isn’t just about the finish line, it’s about enjoying the entire process along the way.

Balancing training and recovery, fuelling your body for endurance, and building strength to prevent injuries are all key components of a well-rounded preparation plan. With dedication and smart strategies, you’ll be ready to conquer the miles and celebrate your accomplishment!

References

Beattie, K., Kenny, I.C., Lyons, M. et al. The Effect of Strength Training on Performance in Endurance Athletes. Sports Med 44, 845–865 (2014). https://doi.org/10.1007/s40279-014-0157-y

Beattie, Kris; Carson, Brian P.; Lyons, Mark; Rossiter, Antonia; Kenny, Ian C.. The Effect of Strength Training on Performance Indicators in Distance Runners. Journal of Strength and Conditioning Research 31(1):p 9-23, January 2017. | DOI: 10.1519/JSC.0000000000001464