Running nutrition is one of the most commonly misunderstood areas of sports dietetics. Many recreational runners significantly underfuel, while simultaneously overcorrecting on race nutrition to the point of gastrointestinal distress. This guide provides the evidence-based approach across all distances.
Carbohydrate requirements for runners
Carbohydrate is the primary fuel for running at intensities above 65% of maximum heart rate — which covers most training runs and all race efforts. Daily carbohydrate targets: 3-5g/kg for moderate training (3-4 sessions weekly); 5-7g/kg for high training loads. These are significantly higher than general population recommendations and substantially higher than the low-carbohydrate diets popularised in some running communities.
Pre-run nutrition
For runs under 60 minutes: a light carbohydrate snack 30-60 minutes before is sufficient. For longer runs and races: a carbohydrate-rich meal 2-3 hours before is recommended. Foods to avoid before running: high-fat foods (slow gastric emptying increases GI distress risk), high-fibre foods (bowel motility stimulation), and unfamiliar foods on race day. Race day is not the time to experiment.
Recovery nutrition
The 30-60 minutes after a hard session or long run is when glycogen resynthesis and muscle protein synthesis are most efficient. A recovery meal providing both carbohydrate and protein within this window accelerates adaptation. Practical options: chocolate milk, Greek yoghurt with banana, or a balanced meal with lean protein and complex carbohydrate. Adequate protein across the day (1.4-1.7g/kg for runners) supports the muscle adaptation that makes training productive.
For more health and nutrition guidance, explore the Vanda's Kitchen blog. Our certified halal, 100% nut-free kitchen at Carter Lane EC4 delivers freshly prepared food to City offices daily. View our team lunch menu or WhatsApp us. Full allergen labelling. Selfridges quality. Corporate invoice accounts. Contact us to discuss your requirements.
Frequently asked questions
Should runners eat before a morning run, and if so what?
For runs lasting under 60 minutes at easy to moderate intensity, running fasted is well-tolerated by many trained runners and will not impair performance meaningfully. For longer or harder morning sessions, a light carbohydrate snack 30-60 minutes before — such as a banana or a slice of toast — provides sufficient glycogen without the gastrointestinal risk of a heavy pre-run meal. Experimenting in training rather than race day is essential for identifying what works individually.
Do recreational runners actually need energy gels for half marathon distance?
At half marathon distance, most recreational runners racing for 2 hours or more will benefit from some carbohydrate intake during the race, as glycogen stores can be partially depleted by this point. However, the quantities used by elite runners are often unnecessary for recreational paces. A gel or two taken with water at the recommended intervals is sufficient for most. Practising gel intake during long training runs avoids gastrointestinal problems on race day.
How important is hydration for running performance, and how should runners gauge their fluid needs?
Even mild dehydration of 2% of body weight reduces running performance measurably, impairs heat dissipation, and increases perceived exertion. Thirst is a reasonable guide for runs under 60 minutes in cool conditions but can lag behind actual needs in hot weather or for longer efforts. Monitoring urine colour — pale straw indicating adequate hydration — is a practical daily check. For long runs and races, planned hydration rather than waiting for thirst is advisable.
Is low-carbohydrate running effective for marathon training?
Some research supports fat adaptation through low-carbohydrate training for improving endurance at lower intensities. However, carbohydrate remains the dominant fuel at race intensities for most runners, and restricting it chronically can impair high-intensity training sessions, increase injury risk through immune suppression, and compromise the quality of key workouts. Periodised carbohydrate approaches — reducing carbohydrate for easy sessions, fuelling key sessions appropriately — have more evidence support than strict low-carbohydrate approaches throughout marathon training.
What should a runner eat the day before a race?
The day before a race should focus on maintaining carbohydrate intake to top up glycogen stores, keeping fibre moderate to reduce bowel unpredictability on race day, and staying well hydrated. Familiar foods are important — no new dishes, restaurant meals, or unfamiliar cuisines. A pasta or rice-based evening meal is conventional for good reason. High-fat, high-fibre, and very large meals should be avoided, as gastric emptying and bowel motility effects can persist to the following morning.