Introduction – Inflammation and the Marathon Runner
As a Sports Nutritionist, I work with many marathon runners who train hard, juggle busy lives, and often push through fatigue in the hope that “more miles” equals better performance.
What’s frequently overlooked is the cumulative inflammatory load of marathon training; long runs, repeated impact, high carbohydrate turnover, limited recovery time and, in many cases, under-fuelling.
Inflammation is a necessary part of adaptation, but chronic, unmanaged inflammation can increase injury risk, impair immune function and disrupt recovery.
This is where an anti-inflammatory nutrition approach can play a strategic performance role rather than being viewed as a wellness trend.
Why Marathon Training Is Inherently Inflammatory
Marathon training places significant stress on the musculoskeletal, metabolic and immune systems. Research shows prolonged endurance exercise increases inflammatory markers such as IL-6 and CRP, particularly when recovery and energy intake are inadequate (Nieman et al., 2005).
Key contributors include:
- High weekly mileage and repetitive loading
- Glycogen depletion and oxidative stress
- Inadequate carbohydrate and protein intake
- Poor sleep and life stress
- Gut irritation during long runs
Left unmanaged, this can lead to missed sessions, illness, niggles and inconsistent training; all of which limit performance far more than a missed interval session.
Can Reducing Inflammation Improve Performance?
The goal of anti-inflammatory nutrition for runners is not to eliminate inflammation entirely as that would blunt training adaptation.
Instead, we aim to:
- Support recovery between sessions
- Maintain immune resilience
- Improve training consistency
- Reduce the severity and duration of post-run soreness
- Support long-term tissue health
Key Anti-Inflammatory Nutrients for Runners
Omega-3 Fatty Acids
Omega-3s (EPA and DHA) help modulate inflammatory signalling and may reduce muscle soreness following endurance exercise.
Sources:
Salmon, mackerel, sardines, trout, algae oil
Research shows omega-3 supplementation can reduce delayed onset muscle soreness (DOMS) and support muscle function in endurance athletes (Jouris et al., 2011).
Studies also suggest that omega-3 fatty acids, may help regulate inflammatory responses, without impairing endurance adaptations when implemented correctly (Fernández-Lázaro, D.,2024).
Polyphenols and Antioxidants
Long runs increase oxidative stress. Polyphenols help neutralise free radicals and support vascular and immune health.
Key foods:
Berries, cherries, leafy greens, beetroot, dark chocolate, green tea
In a research paper, tart cherry juice, was shown to reduce post-marathon muscle soreness and inflammation (Howatson et al., 2010).
There is also some Research on New Zealand blackcurrants (NZBC), particularly anthocyanin-rich extracts, indicating that they can attenuate exercise-induced inflammation and muscle damage, improving recovery in athletes and active individuals. The high anthocyanin content helps manage oxidative stress and inflammation, particularly when consumed daily in the week leading up to a strenuous event. (Hurst, R.D., et al. 2020)
Carbohydrate Availability (Often Overlooked)
Ironically, under-fuelling itself is pro-inflammatory. Low energy availability increases cortisol and inflammatory stress. This is one of the biggest things we see in sports nutrition, an underconsumption of carbohydrates to meet the demands of training.
A well-timed carbohydrate intake:
- Reduces stress hormone release
- Protects immune function
- Limits excessive inflammatory signalling during long runs
This is why anti-inflammatory eating for runners must include sufficient carbohydrates, not restrict them.
Anti-Inflammatory Does NOT Mean Low-Carb
One of the biggest misconceptions I see is runners removing carbohydrates in the name of “clean” or “anti-inflammatory” eating.
For endurance athletes, this often massively backfires.
Carbohydrates:
- Support glycogen replenishment
- Reduce post-exercise inflammation
- Improve recovery between sessions
The focus should be on quality and timing, not restriction; carbohydrates are the energy, not the enemy:
- Whole grains
- Fruit
- Starchy vegetables
- Targeted refined carbs around long runs and races
A Practical Anti-Inflammatory Day for a Marathon Runner
Breakfast
Porridge with berries, banana, honey and a few walnut halves
Snack:
½ bagel with peanut butter and strawberries
Lunch:
Salmon, rice/baked potato, mixed salad, including beetroot, olive oil dressing
Snack:
Greek yoghurt with berries honey and walnuts
Dinner:
Chicken, roasted sweet potato, plenty of veg
Post dinner snack:
Small bowl wholegrain cereal with berries
Hydration:
Water, electrolytes; limit alcohol during heavy training blocks
Common Runner Mistakes I See
- Training hard while under-fuelled
- Excess alcohol during peak mileage
- Ignoring recovery nutrition
An anti-inflammatory approach doesn’t remove convenience, it improves the nutrient density of what you’re already eating.
Q&A
Q: Can an anti-inflammatory diet prevent running injuries?
A: It won’t prevent injuries alone, but it can support tissue health, recovery and immune resilience, which all reduce injury risk.
Q: Should marathon runners take omega-3 supplements?
A: Food sources are the best approach, but supplements can be useful where intake is low – best discussed with a nutrition professional.
Q: Is coffee inflammatory?
A: Moderate coffee intake may actually be anti-inflammatory due to polyphenol content.
Conclusion
For marathon runners, performance isn’t just about VO₂ max or pace charts — it’s about staying healthy enough to train consistently. An anti-inflammatory diet supports the systems that allow you to absorb training, recover efficiently and reach the start line feeling resilient rather than depleted.
References (Harvard Style)
- Annunziata, G., Camajani, E., Galasso, M., Verde, L., Caprio, M., Muscogiuri, G., Paoli, A. and Barrea, L., 2025. Antioxidants and Exercise Performance: Focus on Mediterranean Diet. Antioxidants, 15(1), p.10.
- Fernández-Lázaro, D., Arribalzaga, S., Gutiérrez-Abejón, E., Azarbayjani, M.A., Mielgo-Ayuso, J. and Roche, E., 2024. Omega-3 Fatty Acid Supplementation on Post-Exercise Inflammation, Muscle Damage, Oxidative Response, and Sports Performance in Physically Healthy Adults – A Systematic Review of Randomized Controlled Trials. Nutrients 2024, 16, 2044
- Howatson, G. et al., 2010. Influence of tart cherry juice on recovery following marathon running. Scandinavian Journal of Medicine & Science in Sports, 20(6), pp. 843–852.
- Hurst, R.D., Lyall, K.A., Wells, R.W., Sawyer, G.M., Lomiwes, D., Ngametua, N. and Hurst, S.M., 2020. Daily Consumption of an Anthocyanin-Rich Extract Made From New Zealand Blackcurrants for 5 Weeks Supports Exercise Recovery Through the Management of Oxidative Stress and Inflammation: A Randomized Placebo Controlled Pilot Study. Front. Nutr. 7: 16. doi: 10.3389/fnut.
- Jouris, K.B. et al., 2011. Omega-3 fatty acid supplementation reduces muscle soreness. Journal of Sports Science & Medicine, 10(3), pp. 432–438.
- Nieman, D.C., Dumke, C.L., Henson, D.A., McAnulty, S.R., Gross, S.J. and Lind, R.H., 2005. Muscle damage is linked to cytokine changes following a 160-km race. Brain, behavior, and immunity, 19(5), pp.398-403.
