What to eat before the Sydney Marathon, hour by hour

Sydney is a Major now, which means a lot of people are running their first big-city marathon over the Harbour Bridge this year. The training is the hard part and you have already done it. This is the part people improvise, and improvising is how a good build turns into a bad morning.

The rule that governs all of it

Two days out: load, do not stuff

Carbohydrate loading works, and it is less dramatic than people make it. The target is roughly 7 to 10g of carbohydrate per kilogram of body weight per day for the 36 to 48 hours before the start. For a 70kg runner that is around 500 to 700g a day.

The way to get there is not one enormous bowl of pasta the night before. It is shifting the balance of every meal: more rice, bread, potato and fruit, and correspondingly less fat, fibre and protein than you would normally eat. High-fibre foods are what leave you bloated on the start line, so this is the week to go lighter on salad, legumes and wholegrain.

• Cut fibre back in the final 24 hours. White rice and white bread earn their place here
• Keep protein moderate, around 1.2 to 1.6g/kg, enough to hold the work you have done
• Salt your food normally or slightly more, especially if it is warm
• Expect to gain a kilo or two. Glycogen stores water. That is the loading working, not fat

The night before

Eat early and eat familiar. A normal-sized carbohydrate-heavy dinner at around 6 to 7pm, nothing rich or greasy, nothing you have not eaten before a long run. If you are nervous and cannot face a big plate, this is the one time a sports drink or a bowl of cereal at 9pm is genuinely useful.

Drink to thirst through the evening rather than forcing litres of water. Waking up three times to use the bathroom costs you more than mild under-hydration does.

Race morning, counted backwards

1. 3 to 4 hours before the gun. Your main pre-race meal: 1 to 4g of carbohydrate per kilogram. For most people that is toast with honey and a banana, or porridge made with water, or plain white rice. Low fat, low fibre, no surprises. With a Sydney start this usually means eating around 4am, which is exactly why you rehearse it.
2. 2 hours before. Sip 400 to 600ml of fluid steadily. If it is going to be warm, this is where an electrolyte tablet earns its place: 220mg of sodium in a bottle you were going to drink anyway, with no sugar load on top of breakfast.
3. 60 to 90 minutes before. Stop eating solid food. Last bathroom stop. If you take caffeine, this is the window, roughly 3mg per kilogram, from coffee or a caffeinated gel, and only if you have trained with it.
4. 10 to 15 minutes before the start. One gel with a few mouthfuls of water. This is the single highest-value item on the list: it tops up blood glucose right before the effort starts, and it costs you nothing if you have practised it.

During: 60g an hour, starting early

Aim for 30 to 60g of carbohydrate per hour, and start before you feel like you need it. Your gut absorbs glucose at a ceiling of roughly 60g an hour, so stacking gels late to make up ground does not work. It just sits in your stomach.

A workable Sydney plan for a four-hour runner: a gel at 45 minutes, then every 35 to 40 minutes after that. That is five to six gels, which sounds like a lot until you realise it is around 40g an hour, well inside what an untrained gut manages. Carry one more than you think you need. Course tables are unreliable when you are in a crowd.

Drinking: to thirst, with salt in it

A Sydney winter marathon start is usually cool, which cuts sweat loss and makes over-drinking the more realistic risk. Drinking far more than you sweat dilutes blood sodium, and hyponatraemia is a genuine medical problem, not a theoretical one.

Drink to thirst. If you sweat heavily, leave white salt marks on your kit, or the morning turns warm, put sodium in the fluid rather than drinking more of it. That is what electrolytes are actually for. We have covered where the line sits in electrolytes vs water.

Afterwards

The first hour matters less than the internet says, but it is easy, so take it. Aim for 20 to 40g of protein and a similar or larger amount of carbohydrate within an hour or two of finishing, plus fluid with sodium in it.

The practical problem is that you are in Hyde Park with a medal, not in your kitchen. Something shelf-stable in your bag solves it: a ready-to-eat chicken breast pack is 24 to 26g of protein with no fridge and no cooking, and a protein shake goes down when solid food does not appeal. Then eat a proper meal when you can face one.