The one nutrition rule you should be following: don’t underfuel

When it comes to nutrition, there’s one simple rule you need to follow to make sure you’re fuelling your body, says TCS Sydney Marathon Head Coach Ben Lucas.

This is the time of year when a lot of runners start to get one thing wrong. As the training schedule ramps up and race day approaches, they keep their food intake the same.

That’s when your training can start to unravel.

Are you under-fuelling your runs?

Recently, I’ve been chatting with sports nutritionist Kira Sutherland about this topic, and she’s seeing the same thing I am – more and more runners are drifting into under-fuelling without realising it.

That’s where RED-S (Relative Energy Deficiency in Sport) comes in. Often described as ‘low energy availability’, RED-S is when the body doesn’t have enough fuel, so it starts to cut corners to conserve energy.

This can affect:

• Recovery – slower repair after training

• Hormones – disruptions (especially with menstrual changes in women)

• Bone health – reduced bone density

• Performance – fatigue and plateauing.

In runners, it’s also where stress fractures start to show up. This process doesn’t happen overnight. It builds quietly.

Signs you might be under fuelling your body

Under fuelling doesn’t always show up in obvious ways, but your body will give you clues:

·       You’re constantly tired

·       Runs feel harder than they should

·       You’re not bouncing back between sessions

·       Niggles keep popping up

·       Mood or sleep is off

These might not be isolated symptoms, they may be your body telling you something.

The simple rule to follow

The general guideline is: as your training load increases, your fuelling needs to increase with it. Tools like the GU fuelling calculator can be helpful as a guide, but don’t overthink it.

Eat properly.

Fuel your runs.

Recover.

Under-fuelling might feel like you’re getting leaner or ‘lighter’, but long term it can cost you performance and consistency. You don’t get fitter from the session. You get fitter from how well you recover from it.

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