With marathon season in full swing, fewer than 20 days remain until over 50,000 runners converge on Greenwich for the iconic London Marathon. Scheduled for April 27, 2025, the gruelling 26.2-mile course will conclude in front of Buckingham Palace, demanding months of disciplined preparation. Whether it’s your first or tenth marathon, a strategic approach to training is vital. To guide runners, Kerry Beeson, nutritional therapist at Prep Kitchen, and Dr Hana Patel, resident sleep expert at Time4Sleep, offer evidence-based insights on how diet and rest can enhance performance.

Nutrition forms the backbone of marathon preparation. Beeson, an expert with a BSc in nutritional medicine, outlines four key food groups runners should prioritise. “Complex carbohydrates are best as they are metabolised more slowly than simple sugars, providing sustained energy without causing blood sugar peaks and troughs,” she explains. She recommends 5-8g of carbs per kilogram of body weight daily, depending on training intensity. Protein, she adds, is “essential for muscle growth and repair, and for the production of enzymes which aid nutrient absorption.” Healthy fats, found in oily fish, olive oil, and avocados, serve as an anti-inflammatory secondary energy source, while fruits and vegetables – especially antioxidant-rich options like berries and beetroot – bolster immunity and aerobic capacity.

Equally critical is knowing what to avoid. Beeson highlights three food types that could derail progress. “Your diet should be very efficient when training—every meal needs to count,” she says. “Processed foods are typically full of empty calories, added sugar, and fat, with low amounts of the nutrients your body needs.” Fatty foods, such as deep-fried items, digest slowly and may leave runners feeling sluggish. High-fibre options like beans and cruciferous vegetables, though healthy, can cause bloating and should be skipped before training or race day.

Timing meals around workouts is another key factor. “If you like an early morning run, eat well the night before,” Beeson advises. “For longer runs, however, it’s always best to do this when fuelled up – have a balanced meal 2-3 hours before, then a carb-heavy snack about an hour before.” This approach ensures energy reserves are primed without overloading the stomach mid-run.

Sleep, often overlooked, is just as crucial. Dr Patel, a sleep expert with Time4Sleep, underscores its role in recovery and performance. “Sleep plays an important part in an athlete’s recovery process and their performance, which is one of the reasons why there has been an increase in sleep monitoring for elite athletes,” she says. For marathon runners, slow-wave sleep restores muscles fatigued by long-distance training, while also sharpening mental alertness for race day. The NHS advises finishing vigorous exercise two to three hours before bedtime to allow the body to unwind, a recommendation Dr Patel echoes. “Instead, choose a relaxing form of exercise, like yoga, if you will be exercising close to your bedtime,” she suggests.

Top tips for optimal marathon sleep

• Establish a consistent routine. Go to bed and wake up at the same time daily where possible.
• Unwind before bed. Meditation or mindfulness can ease you into sleep.
• Optimise your environment. Keep your bedroom cool, dark, and quiet.
• Choose supportive bedding. Select a mattress, pillows, and bed size that ensure comfort.
• Avoid forcing sleep. If rest doesn’t come, step away for a calming activity before trying again.