I stress these are my personal views based on what works for me. My approach is based on the science behind nutrition for endurance activities but it is like everything else in life, you have to establish what works for you. Distance, ability to utilise fat stores for fuel, flavour fatigue and decisions regarding hydrating to thirst or by time are all variables you need to determine, train and test during your preparation for ultra-distance courses. If these notes help anyone, I’ll gladly expand on them in further posts and happy to take questions!


Ultramarathons are footraces that surpass the standard marathon distance, and include popular distances of 50km, 80km and 100km, etc. Single stage, multi day and multi stage may be terms you have come across but I’ll focus on the single stage in this piece.

Most will know that a minimalist approach to nutrition can be adopted on distances up to Marathon level but we increasingly see fuelling via gels and sports drinks etc. being used on shorter form racing.

However, good nutrition and proper hydration have an essential role to play in completing ultra-distance events, whether single-stage or multi-stage. Since ultra-distance marathon events take different formats, from circuits on a level surface to a hilly terrain like cross-country, it is important to put into consideration the duration, altitude, topography of the track, sweat rate, distance, and access to fluid and food when determining your nutrition and hydration plan. Events often require more hours and tremendous effort to train; thus, nutrition is an integral component of the preparation phase and ultramarathon runners should aim to meet both caloric and hydration demands and practice how best to satisfy these during training ahead of race day. It is very critical to take into account the nutrition during the training period and ensure you are having adequate food to fuel and recover well. The best training diet will vary depending on the type of the event, your own tolerances and distances to be covered. In my view, the nutrition aspect of greater importance includes the following; Energy/fuel, Protein and muscle repair, and hydration.

Energy/Fuel and Macronutrient

To meet the energy demands for a prolonged and circuit training session, the amount, type, and timing of energy foods is key. Eating more consciously on the days that you train for longer periods as well as the recovery days will help prevent energy deficit thus improving performance and endurance.

Daily caloric requirements are influenced by several factors, including resting metabolic rate, daily activity level, specific training requirements, and body composition. For endurance training, most evidence shows that energy from carbohydrates should amount to nearly 60% or 5-8g/kg body weight, 25% from fat, and 15% from protein or 1.3-2.1g/Kg. Since fat is more energy-dense, it is prudent to maximise fat oxidation to spare liver and muscle glycogen storage for the later stages of an ultra. One way of achieving this is by refraining from consuming carbohydrates for approximately 90 minutes after starting your session. Another means of enhancing the body’s capacity to burn more fat is to train or exercise in a fasted state before breakfast. Something I do but something that takes time to adjust to. However, caution should be exercised in terms of performing sessions in a chronically carbohydrate depleted state. For high-intensity training for a longer period, full glycogen stores are recommended. Thus, a carbohydrate consumption of about 5-8g/kgbwt per day is encouraged. And… as a side note for those enjoying ketogenic diets, the jury is still out on the value of these for ultra-events due to the lack of evidence but if what you are doing now in this domain works for you, build your plan accordingly.

Energy intake before an event

I personally aim to minimise calorie deficits beforehand by carbohydrate loading two days prior to the start. I aim for around 8-10g per lkg of body weight.

Energy intake during an event

It should be obvious that the caloric requirement for a longer race is higher than in short races. Hence, aim to consume more calories as tolerated. An intake of 150-300kcal/hr is recommended for up to 80kms while 200-400kcals/hr for longer races. I personally always fall just below this but find my performance picks up when I can adhere to it.

Protein and muscle repair

The longer duration and distances increase the risks of injuries to the muscles and tendons. The stress on muscles, tendons, and ligaments is even more aggravated by rugged terrain or hilly running. Protein intakes of 1.6g-2.1g/kg body weight are necessary to maintain lean muscle mass and promote tissue recovery resulting from training injuries. More protein of up to 2.5g/kg can be warranted in case of increased calorie requirements due to demanding training. It is ideal to eat a moderate amount of protein throughout the day rather than large portions at one time or two meals. A recommendation of 20g of protein intake every three hours is optimal. Vegetarians who have a higher propensity for not meeting their protein requirements can be supplemented with a plant-based protein powder supplement.


Adequate fluid in the body prevents tissue injuries and enhances the overall performance. It also helps in maintaining a proper balance of electrolytes in the body. Thus, it is very important to replace fluid losses during and after training. Preferably slowly consume more fluid than the amount lost through sweat and urination. International Society of Sports Nutrition (ISSN) recommends 150-250ml of fluid every 20 minutes.

Want to know more? Have questions? Drop me a line at i@raceultras.com and I’ll get back to you on a best endeavour basis.