Marathon Fever Nutrition
Were you inspired by the amazing people running the London marathon this weekend? Have the floods of marathon finishers’ Instagram posts motivated you to lace up your running trainers? This blog will take you through the key nutrition components for success in your training and future races!
The building blocks of endurance
Macronutrients
- Carbohydrate
- Protein
- Fat
The macronutrients each play a key role in our daily nutrition. When exercising, the balance of these nutrients throughout the day becomes more important (1).
Micronurients
For the general population it is important to follow dietary guidelines for micronutrients, which can be achieved by eating a healthy and balanced diet.
Hydration
The increase in fluid loss as a result of sweat occurs as a result of increased body temperature – a natural body mechanism to help the body cool down. Sweat rate increases with exercise as our heart rate increases. This means as we exercise more and sweat more, keeping hydrated becomes more important! (2)
More general information on these nutrients can be found in our previous blogs.
Fuelling Strategy
Pre-Run Nutrition:
- Carbohydrates pre-workout for endurance should be the key focus in order to boost the energy stores and aid performance
- Carbohydrates are the main fuel source for exercise – our dietary carbohydrates are converted to glucose and stored as glycogen to help fuel muscle contraction and movement. Higher intensity exercise such as running uses blood glucose and muscle glycogen stores to make the energy to power muscles for movement (3)
- Make sure larger meals are consumed 1-2 hours before your run to allow for digestion and prevent stomach issues during your run.
- Hydration – make sure you are hydrated before starting your run, ensure fluids have been taken on with your pre-run meal– the easiest way to keep track is to make sure your urine is light in colour!
Examples:
Sweetcorn potato fritters
Bagel with banana and honey
Bagel with hummus
Baked oats
Keep your eyes out for our upcoming balanced healthy recipe cards you could use in your nutrition plan!
During Run Nutrition:
Nutrition during your runs will differ depending on the intensity and duration
When exercising at a lower intensity for a short period of time, it is likely that fuelling before and after your exercise will be sufficient
Higher intensity and longer duration runs is where fuelling and hydrating during can be beneficial for performance, health and injury prevention
Unfortunately our energy is not unlimited! Our bodies can only store a limited amount of glycogen in our body and eventually our stores are depleted.
Consuming easily absorbable carbohydrates during a training run and race can help to slow the depletion of these stores and extend our bodies ability to keep going! (3)
For exercise longer the 60 minutes the recommended intake is to consumed 30-60g of carbohydrates per hour e.g. 1-2 energy gels (depending on carbohydrate content) or 6-10 jelly babies. (1)
In prolonged events lasting 2.5 hours or more, recommendations aim for a higher 90g per hour intake of carbohydrates. (1)
Consuming simple carbohydrates that are easily absorbed is key here to help to maintain energy and prevent stomach upset.
TRAINING: it is important to test the type, amount and timing of carbohydrate intake throughout your training runs before heading into a race as there are individual factors that affect a persons ability to consume carbohydrates and it is important to get the body used to the process before a race.
RACE: practice makes perfect – try to keep to what you have practiced in training – You don’t want your race derailed by stomach upset!
Examples:
- Jelly cubes
- Energy gels
- Chewy sweets
- Carbohydrate drinks (hydration & carbohydrates)
Top tip: try out different forms of nutrition during training to find the best fit for your stomach and taste buds!
Post-Run Nutrition:
- After your run refuelling is key for recovery – injury prevention and readiness for your next workout
- Refuelling with a balanced diet is best to make sure carbohydrates are eaten for energy store replenishment and protein source for muscle growth and repair
- Rehydrate! It is likely that after an endurance run your body will need rehydrating to replenish the water and electrolytes lost during exercise – this is especially important if you are a heavy sweater, in hot/humid environments or if your urine is dark in colour! (1)
- Rest & Refuelling go hand in hand
- Make sure you are resting alongside your refuelling to allow for your body to adapt to the training load, replenish the muscle glycogen stores and maxmise muscle damage recovery. (4)
Post race: A race tends to bring higher intensity levels whether you are posting a personal best time, distance or generally enjoying the race. The crowds, the nerves and pounding on the streets means our bodies are likely to need a longer period of rest before getting back to normal scheduling
Examples:
- Poached egg and avocado on toast
- Crispy rice chicken salad
- Banana oat pancakes with Greek yogurt
- Egg and sausage on wholemeal toast
- Tofu scramble with tomatoes on bagel
Healthcare Professionals
Over the last 5-10 years there has been a boom in the popularity of running with 1.1 million people applying to the London marathon public ballot for the 2026 race (5)! This increase in the uptake of running also increases the demand for nutritional support for these athletes.
As sports nutritionists there are nutrients which should be taken into consideration for each athlete and may vary depending on age, sex, sport type and intensity. The tracking of these nutrients can be difficult, especially when working with recreational athletes who may not be as aware of nutrients within food and often have less time to focus on nutrition.
Tracking the key nutrients, including those outlined in the ACSM (1), can be carried out in myfood24, using our healthcare system.
Key Nutrients x myfood24
Examples of nutrients in myfood24 that are essential to nutrition for recreational and professional athletes as per the ACSM position statement (2016):
Iron & Performance:
- Important to be meeting the government recommendations
- Iron is key for muscle function and work capacity, therefore iron deficiency would negatively affect sports performance
- There are some common factors that can negatively impact iron status such as blood donation, high altitudes and menstrual blood loss
Vitamin D & Performance:
- Regulates calcium and phosphorus absorption and metabolism as well as bone health
- Associated with injury prevention, reduced inflammation and reduced risk of stress fracture
Calcium & Performance:
- Growth maintenance and repair of bone tissue, regulating muscle contraction, nerve conduction and blood clotting.
In myfood24: government targets are incorporated into the system and can be adjusted if necessary on an individual basis.
Our reports represent the key target nutrients in multiple ways, allowing healthcare professionals to make customised reports for each athlete depending on their set targets, goals and dietary intake.
References
- Nutrition and Athletic Performance. Medicine & Science in Sports & Exercise 48(3):p 543-568, March 2016. | DOI: 10.1249/MSS.0000000000000852
- Wei et al., 2024. The science of hydration: its impact on endurahce and performance in athletes. Journal of Sport Psychology.
- Williams et al., 2007. Carbohydrate as an energy source for sport and exercise. Nutrition and Sport.
- London Marathon considers two-day event in 2027. BBC Sport March 2026. Available via: https://www.bbc.co.uk/sport/athletics/articles/cqxl8yn4gxwo
- Mielgo-Ayuso & Fernández-Lázaro, 2021. Nutrition and Muscle Recovery. Nutrients.
Author: Lucy Clarkson, SENr Nutritionist
Editor: Jessica Eardley-Thompson, ANutr Nutritionist & Grace Williams, ANutr