From my own personal experience, I am a regular runner who, without fail, will feel faint or sick if I run on an empty stomach, whether it’s 5k or 21k. And a carby item of some description is usually just what I need to avoid that.

“Fuelling before a run provides your body with the energy it needs to work and perform efficiently and safely,” says Sarah Campus, a runner, PT and nutrition coach. “Eating pre-run helps maintain blood sugar levels, which supports muscle function and prevents early fatigue, dizziness or weakness.”

It’s also important to fuel properly, as this allows the body to rely less on muscle breakdown for energy. She says that fuelling effectively “improves endurance, focus and overall performance while also reducing the risk of feeling drained during or after the run”.

Interestingly, men and women’s nutritional needs differ. So, when a man says, for example, “I always run my 10ks on a droplet of rainwater and a teaspoon of creatine,” it’s completely irrelevant to a woman’s needs.

“Men and women differ in pre-run fuelling needs mainly due to differences in hormones, body composition and metabolism,” Campus says. “Women tend to rely more on fat as a fuel source and are more sensitive to low energy availability, so they often benefit from more consistent carbohydrate intake before running to support blood sugar levels and hormonal balance.” So, something like a bagel and a banana makes for great pre-run fuel.

Campus adds that while men generally have higher muscle mass and higher energy demands, they are typically less affected by short-term energy deficits. She says: “If women under-fuel before a run, this can quickly lead to fatigue, reduced performance and disrupted menstrual or bone health, making adequate pre-run nutrition especially important.”

So, why would you want to risk that?

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