Sydney is not a flat marathon. The course undulates, and undulation changes the fuel maths: repeated climbs push you above threshold in short bursts, and each burst leans harder on carbohydrate than steady running at the same average pace would.
The practical consequence is simple. A runner who fuels a hilly marathon like a flat one arrives at the last 8km with a deficit they cannot repay. Build the plan around a higher carbohydrate rate than you would use on a flat course, and rehearse it in training on similar terrain.
What the race demands
Course
Undulating city course with bridge and harbour climbs
Season
Late winter to early spring, mild and variable
Main risk
Climbs spiking carbohydrate cost above your planned rate
Second risk
Downhill sections loading the quads before the final kilometres
Carbohydrate and sodium targets
- Sub-3:00: 70 to 90g of carbohydrate per hour from a dual-carb source
- 3:00 to 4:00: 50 to 75g of carbohydrate per hour
- 4:00 to 5:00: 40 to 60g of carbohydrate per hour
- Sodium: 300 to 800mg per hour depending on your measured sweat rate
HYDRAX CORE delivers 85g of dual-carb fuel and 980mg of sodium per serve, so hitting the numbers above is arithmetic rather than guesswork. HYDRAX PRIMER covers the pre-race window with 29g of carbohydrate and 1,313mg of sodium. Run the free fuelling strategy tool to convert these ranges into your own per-hour numbers.
Rehearse the plan in training, then race it. Order now, ships Australia-wide.
Race week and race day timeline
2 to 3 days out
Carb load toward 8 to 10g per kg per day. Keep fibre low in the final 24 hours.
Race morning, 3 hours out
Rehearsed breakfast, 1 to 2g of carbohydrate per kg. No new foods.
25 to 40 minutes out
One serve of PRIMER for pre-loaded carbohydrate and 1,313mg of sodium.
From 30 minutes in
Fuel with CORE at your target rate. Take it on the flat sections, not mid-climb.
Final 10km
Keep taking carbohydrate even when appetite drops. The late hills are where the plan pays.
Frequently asked questions
How do hills change marathon fuelling?
Climbs push you above your steady-state effort in repeated bursts, and higher intensity shifts fuel use toward carbohydrate. On an undulating course like Sydney, aim toward the upper end of your carbohydrate range rather than the middle, and take fuel on flat or downhill sections where your gut is under less pressure.
What should I eat before the Sydney Marathon?
A familiar high-carbohydrate breakfast around 3 hours before the start, 1 to 2g of carbohydrate per kg of body weight, then a pre-race serve 25 to 40 minutes before the gun. Race morning is not the day to test a new food.
How much sodium do I need for the Sydney Marathon?
Between 300 and 800mg per hour for most runners, driven by your sweat rate rather than the forecast. Measure it in training. HYDRAX CORE provides 980mg per serve.
When should I start fuelling?
By the 30-minute mark. Waiting until you feel low means you are already behind, and on a hilly course the deficit compounds faster.
Keep reading
- Marathon fuelling strategy
- Carbs per hour for a marathon
- Carb loading for race day
- Running pace calculator
Disclaimer: This page is general information for healthy adult athletes and is not medical, dietetic or coaching advice. Individual carbohydrate, fluid and sodium requirements vary with body weight, sweat rate, conditions and health status. Speak with your doctor, sports physician or an accredited sports dietitian before changing your nutrition or supplement routine, rehearse any fuelling plan in training before race day, and always follow the directions and warnings on the product label.