babylon's guide to a healthy marathon

Running a marathon is an amazing goal, and if you’re running for charity you have the opportunity to help a number of people. However, it’s hard to ignore that running 26.2 miles in one hit puts your body under enormous physical strain. Don’t let a health problem colour or jeopardise your achievement, follow our guide and make sure you’re fighting fit at the finish line.


3 weeks to go

Reduce your weekly mileage by 15%

It’s important at this point to start tapering your training to maximise efficiency on the day. You need to confidently cut your running distances while maintaining intensity, giving your body time to recover. At three weeks you can achieve this by giving yourself an extra rest day, or by simply cutting down your recovery runs by 2 – 3 miles.  


2 weeks to go

Reduce your mileage to 70-75% of your maximum

You should also reduce your long run to 50-60%. With two weeks to go you can’t gain any more fitness, but you can tire yourself out. If you feel fatigued, don’t be afraid to lower your mileage still further. The distance of this run is far more to do with psychology than it is to do with anything else.


1 week to go

Reduce your mileage on every run to 50-60%

This is tough and psychologically challenging, but it’s important to allow your body recovery time before the day. To remind your body what marathon-pace feels like, do a session that includes a 15-20 minute warm-up, 6-8 x 2 minutes at marathon pace, with 2 minutes of easy running in between, with a 10-15 minute cool down. This session won’t leave you exhausted, but it will give you the confidence you need at this stage.

Do a 1-3 mile easy-run the day before the marathon. This will help with blood flow to your legs and stimulate your central nervous system, which will help your legs to respond better and faster the following day.


On the day

Eat breakfast

Your body needs to maintain activity, and it’s important to give it the fuel to do so. Make sure you head to the starting-line having eaten a carbohydrate rich breakfast.

Wear well-worn shoes and gear

You don’t want to be running in new gear for the first time on the day of the marathon. Make sure you know and have tested your equipment.

Save it for the race

Don’t run before a marathon or walk a couple of miles to the starting line. You’ve got a long way to go, so save your energy.

Eat carbs during

Your body stores enough carbohydrate to keep you at sustained activity for roughly two hours. As you’re probably not world-class level you will be running for longer than this. Make sure you fuel-up during to maintain blood-sugar levels and delay carb depletion.

Hydrate early and often

Dehydration causes your speed to drop drastically. Start hydrating early and often to avoid this.

Pace yourself

Avoid extreme changes in pace. The least taxing way to run a marathon is to run the first and second halves in the same time, or run the second half very slightly faster than the first.


What to watch out for

If you’re feeling significantly nauseous before running, or if you experience any chest pains during your training, seek medical advice. It’s important not to ignore the little signs that could lead to serious health complications, especially when you’re pushing yourself to the limit. babylon GPs are available in minutes wherever you are, so if you’re worried for whatever reason, book a consultation.


Staying in good health

Make sure you get plenty of sleep, and eat healthily on the lead-up to a marathon. During the three days leading up to the race, eat plenty of carbs. Concentrate on pasta, potatoes, bread, fruit and fruit-juice, low-fat milk and yoghurt, and sports drinks. It’s carbohydrates you want, not fat. Don’t eat more than usual, just choose foods that will maximise your energy input.

Don’t coffee-load before the race, keep it to one small cup about two hours before you start.

If you suffer from a sensitive stomach during a race, carry a small role of Peppermint Tums or a similar product with you.



Recovery is critical and often neglected. If you don’t recover from your marathon you will increase your risk of injury and limit your long-term potential.

Skeletal muscle

The inflammation and muscle fibre necrosis in the calves, caused by training and the marathon itself, significantly lowers muscle power and strength for up to 14 days post-race.

Cellular Damage

Oxidative damage and creatinine kinase (CK), an indication of damage to skeletal and myocardial tissue and increased myoglobin levels in the blood stream (often resulting in blood in your urine), can persist for more than 7 days post-marathon.


After running 26.2 miles your immune system is severely compromised, increasing your risk of contracting colds and flu. Your immune system is compromised for 3 days after a marathon, and in that time it’s important to rest as much as possible and eat vitamin-rich foods.

It’s worth taking a hot bath for 10-15 minutes every day, followed by a stretch, for 3 days after you’ve run a marathon. This will help your muscles to relax and recover.


Good luck! And for those moments when you need a doctor’s advice, our GPs are available 12 hours a day, wherever you are.