Fuelling on the Trail: What to Eat and When
Training Notes · Nutrition
Fuelling on the Trail
What to Eat and When
For many runners, fuelling is something that sits on the edge of training.
Something to think about later. Something to test closer to race day. Something that matters, but not as much as the running itself.
This is where most mistakes begin.
Fuelling is not separate from training.
It is part of the stimulus.
You are not just training your legs. You are training your ability to take in and use energy while you run.
Why Fuelling Matters More Than You Think
Endurance performance is not limited by fitness alone. It is limited by how much energy your body has available, and how efficiently it can use it.
As training load increases, so does the demand for fuel. Without it, the body compensates.
Research in female athletes shows that under-fuelling elevates cortisol, suppresses thyroid function, and impairs both recovery and adaptation.
This is not just about feeling tired. It changes how your body responds to training.
Runs become harder than they should be. Recovery takes longer. Progress slows.
Over time, this compounds.
When to Start Eating
One of the most common mistakes is waiting too long.
By the time you feel depleted, you are already behind.
A simple structure works for most runners.
Simple fuelling structure
Start eating at 30 minutes
Continue every 30 minutes
Adjust slightly based on intensity and duration
This is not about precision. It is about consistency.
What to Eat
Fuel needs to be practical.
Something you can carry. Something you can tolerate. Something you can repeat.
For most runners, this includes:
Gels or chews
Simple carbohydrates (bananas, dates, bars)
Liquid fuel options
There is no single perfect option. The goal is to find what works for you, and practise it consistently.
Training Your Gut
Your ability to fuel is trainable.
The gut adapts in the same way your muscles do. Repeated exposure improves tolerance and efficiency.
This is why fuelling should be practised in training, not saved for race day.
Start simple. Stay consistent. Build gradually.
The goal is not just to carry fuel. It is to be able to use it.
What It Should Feel Like
When fuelling is working, the difference is subtle but clear.
Energy feels more stable. Effort is easier to hold. There are fewer peaks and troughs.
When it is not, you may notice:
A drop in energy late in the run
Difficulty maintaining effort
Increased perception of fatigue
Longer recovery after sessions
These are not just signs of a hard session. They are often signs of under-fuelling.
The Female Physiology Layer
For women, fuelling carries an added layer of importance.
Lower energy availability impacts hormonal health more quickly, and with greater consequence.
Consistent fuelling supports not just performance, but recovery, mood, and long-term training capacity.
It is not about eating more than needed. It is about eating enough for the work you are asking your body to do.
The Shift
At some point in training, fuelling stops being optional.
It becomes part of how you train.
Not something extra.
Something essential.
