Why you can trust Nutri Advanced  Every article on our site is researched thoroughly by our team of highly qualified nutritionists. Find out more about our editorial process.

  • Marathon training demands more than casual runs; proper gear, schedules, & nutrition are vital.
  • Supplements aid vitamin/nutrient levels depleted by intense training, supporting recovery & performance.
  • Key supplements include multivitamins, iron, omega-3, curcumin, and ashwagandha for endurance & recovery.

Is training for a marathon on your bucket list, or maybe you are already deep into training for this year’s London Marathon. Wherever you are on your training journey, completing a marathon is a huge achievement, even if you are a regular long-distance runner, and is something that shouldn’t be taken lightly. Covering the distances required to prep for a 26-mile run involves much more than for a long run around the local park on a Saturday afternoon; you’ll require different gear, a strict training schedule – and, you’ll need to consider the way you are fuelling your body in order to limit strain.

The best supplements for marathon running, or the best supplements for marathon training, are simply those that will increase the levels of the vitamins and nutrients you already get from a balanced diet along with nutrients that aid in recovery. Intense exercise can deplete these levels, making you more susceptible to injury, slower recovery, or hitting a training plateau. By adding a supplement into your daily regimen, you can ensure that your body is getting everything it needs in order to get the most out of your marathon running. Even for regular long-distance runners, completing a marathon is a huge achievement, and something that shouldn’t be taken lightly. Covering the distances required to prep for a 26-mile run involves much more than for a long run around the local park on a Saturday afternoon; you’ll require different gear, a strict training schedule – and, you’ll need to consider the way you are fuelling your body in order to limit strain.

So, what are the best supplements for marathon runners?

Do marathon runners need supplements? 

In short – no. No one needs supplements - you can get all the nutrients you need by following a healthy diet plan for men or women. However, when participating in an exercise like marathon running, which goes on for a long period of time, it’s important to understand which nutrients your body will need the most.

So, when it comes to supplements for marathon runners, the best place to start is by understanding which vitamins and nutrients play a role in your exercise, and which might need a top-up to support your training.

Why do marathon runners consider supplements?

Unlike high-intensity workouts like weightlifting, running is all about endurance. Unless you can keep running at a decent pace for miles on end, you’re probably not getting the most out of your workout. Running, especially for long distances, takes your body to the limit of its endurance capabilities and then will push it even further. Of course, this also means that when you’re out running, you’ll need enough energy in reserve to keep pushing your limits.

Adding supplements to your diet will help your body to keep going mile after mile, hour after hour. Focussing on vitamin supplements for marathon runners will help you to be confident in the knowledge that you are putting the most into your training – and getting the most out of it.

What supplements do marathon runners take?

We’ve already taken a look at the best supplements for runners – but, marathon running is different: it’s longer, requires more endurance, and will take more out of you. So, the best supplements for marathon training will be slightly different.

The best supplements for marathon runners are ones that will help to support your body during long runs, and ones that help you restock to allow your body to recover during an arduous training schedule. In addition, beverages like electrolyte and caffeinated drinks will help you to support your performance, and help your body cope with the demands of marathon training.

Best supplements for marathon runners

Multivitamins

Vitamins play a key role in nutrition, particularly when it comes to the best supplements for marathon training. They play a big part in endurance; vitamin C and B vitamins for example can help fight fatigue. Vitamin B12 is required for energy production in cells and because vitamin B12 can only be found naturally in animal products, runners who follow a vegan or vegetarian diet may particularly benefit from taking a multivitamin to maintain energy levels.

Glutamine

Running, and any other endurance exercise, will deplete glutamine levels in your muscles and blood stream. And, as glutamine acts as fuel for immune cells, your immune function will be limited if your levels decrease.

L-Carnitine

L-carnitine helps your body to transfer long chain fatty acids to be oxidised for energy production, powering muscle contraction. It helps to provide your body with extra energy, and is used by a variety of different athletes to support performance.

Omega-3 fatty acids

We recommend omega-3 to everyone – not just marathon runners. It helps to support your heart, brain and vision, as well as benefiting joint health. Therefore, it’s a crucial feature on our list of best supplements for marathon running. This is a nutrient our bodies don’t naturally produce, so the only way we can get what we need is by eating oily fish, or taking a supplement.

Iron

Iron is an essential nutrient, which means it must be consumed because we can’t manufacture iron internally. Vegetarian and vegan runners are at an increased risk of lower iron levels because the richest and most readily absorbed sources of iron are from animal meats. If you are a marathon runner, adding an iron supplement could be useful, particularly if you are vegetarian or vegan, your diet is low in iron, or you have higher requirements e.g. women in their reproductive years.

Calcium

No list for any runner would be complete without calcium. Calcium is crucial in the support of bone health, and considering running puts a lot of stress on your skeletal structure, it’s important to ensure you are getting your recommended daily amount.

Zinc and magnesium

When it comes to the best supplements for marathon runners, zinc and magnesium have to make the list. Magnesium helps to transport energy around your body, and zinc helps you to metabolise energy so you can put it to good use.

Curcumin (turmeric)

Due to the arduous nature of training for a marathon, injury and pain can happen regularly and impact your training schedule and performance. Many athletes rely on pain killers in times of extensive training. Curcumin is a natural compound and has been studied extensively for its analgesic (pain relieving), anti-inflammatory & antioxidant properties. Several clinical trials have found 150-180mg/d of curcumin reduced the impact of DOMS in untrained individuals after resistance training .1

Boswellia

Boswellia, (also known as frankincense) a natural extract from the Boswellia serrata tree, has been extensively studied for its joint protective, anti-inflammatory, analgesic (pain-relieving), and antioxidant properties.2,3 Due to its ability to reduce joint pain & improve mobility, clinical trials have investigated how this might impact athletes suffering from high-impact joint pain post extensive exercise.

The study demonstrated that consumption of standardized Boswellia serrata extract before, during, and after repeated bouts of high-impact exercise significantly improved subjective measures of soreness, accelerated functional recovery, and decreased inflammation-related biomarkers compared to a placebo.4

Ashwagandha

Ashwagandha is a traditional ayurvedic herb known to increase energy and support the stress response. If you are a marathon runner, adding an ashwagandha supplement could be useful as it helps increase the capacity of the blood to transport oxygen to exercising muscles to enhance your performance.

Marathon running with Nick Bester

We have been lucky enough to have a chat with Nick Bester, a seasoned marathon runner with over 50 marathons under his belt. Discover what Nick thinks about marathons, training, and what the best supplements for marathon runners are.

Can you introduce yourself to our readers?

I’m Nick Bester, also known as ‘justalilbester’. I’m an athlete and a running coach. I’ve made it my mission to try and break 2h 20m in the marathon distance, which I conquered at the Berlin Marathon 2024. I started an athletics club in the UK called Best Athletics. It was registered just under two years ago and there are currently over 600 members, a club I’m very proud to be a part of and represent. I am also a coach and London captain for Adidas.

What does a typical week of training look like for you in the lead-up to a marathon?

Monday: Easy double run & strength
Tuesday: Track/interval session
Wednesday: Easy run
Thursday: Tempo or hills & strength
Friday: Easy run or rest day
Saturday: Marathon specific long run
Sunday: Easy day

Total mileage for the week between is usually 150-200kms.

How do you fuel your body before, during, and after long runs?

  • For my important runs I carbo load from the night before.
  • Start well hydrated (electrolytes, hydration tablet and carb drink mix).
  • Eat breakfast 1.5 - 2 hours before.

I aim to get in around 60-100g of carbs per hour of exercise through a combo of gels, drink mix and solids.

What strategies do you use to prevent injuries during your training?

Easy days easy and hard days hard. I aim to get in at least 8 hours sleep, and strength work at least twice a week. Give my body the fuel and nutrition it needs.

How do you mentally prepare for the challenges of running a marathon?

I choose a race song for each race and when that plays, I run through different scenarios on race day so that when they happen I’ve mentally prepared for them.

What are your go-to recovery techniques after a particularly gruelling run?

I usually have a combination of sports massages, massage gun, foam rolling, and recovery exercise routines within my training week to lose up tighter muscles. I always make sure to get in 20-40g recovery protein after my runs.

Do you have any specific rituals or routines on race day to ensure you're at your best?

  • Listen to my race song to get me in the race mindset.
  • Write split times down on my arm.
  • Soak up the race day vibes and let them fuel me!

How important is sleep in your training regimen, and how do you ensure you get enough rest?

Sleep is the most important form of recovery. I always aim to give myself at least 8 hours sleep, and an extra hour in race week.

What keeps you motivated during the toughest parts of your training and the marathon itself?

Thinking about the ‘why’ I run. Knowing that whatever work I put in during those moments when it’s getting tough, I’ll thank myself for post-race.

Do you stick to a strict nutrition plan? If so, do you take any vitamins or supplements?

I don’t follow a nutrition plan specifically, but I try keep my diet clean especially during vigorous training and then the buildup to race. I’ll take the following vitamins and supplements on a daily basis:

  • Recovery protein within half an hour of the session.
  • Hydration electrolyte tablets.
  • MegaMag® Muscleze before bed.
  • Omega-3, vitamin B, vitamin D and calcium.

If you could give nutritional advice to a new marathon runner, what would it be?

Give yourself the sufficient amount of fuel your body needs. Fuelling correctly is as important as training. If you get your fuelling right, you’ll feel way better in sessions, hit better times, and speed up overall improvement. The two bits of nutrition I take daily, religiously, without fail, is recovey protein after sessions, and MegaMag® Muscleze before bed. Look after your body, and it will look after you.

References:
1. Fang W, et al. Phytother Res. 2021 Apr;35(4):1768-81. doi: 10.1002/ptr.6912​
2. Haroyan A, et al. BMC Complement Altern Med. 2018. doi: 10.1186/s12906-017-2062-z​
3. Mahdian D, et al. Iran J Basic Med Sci. 2020. doi: 10.22038/ijbms.2020.42115.9957​
4. Salter, D., Yalamanchi, H., Yalamanchi, A., and Yalamanchi, A. (2025) 'Ten days of supplementation with a standardized Boswellia serrata extract attenuates soreness and accelerates recovery after repeated bouts of downhill running in recreationally active men', Frontiers in Sports and Active Living, 7. Available at: https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2025.1488821/full (Accessed: 20 March 2025).

This website and its content is copyright of Nutri Advanced ©. All rights reserved. See our terms & conditions for more detail.

Nutri Advanced has a thorough research process and for any references included, each source is scrutinised beforehand. We aim to use the highest value source where possible, referencing peer-reviewed journals and official guidelines in the first instance before alternatives. You can learn more about how we ensure our content is accurate at time of publication on our editorial policy.