Zone 2 and fat burning
Zone 2 is undoubtedly one of the most used training terms in 2025. For many exercisers and ambitious amateurs, it has become synonymous with “easy training”, fat burning and long rides with a low heart rate. But while Zone 2 sounds simple, it is also one of the most misunderstood forms of training.
When done correctly, Zone 2 training is an extremely effective tool for:
- improve fat burning
- strengthen the heart
- increase aerobic capacity
- create a solid foundation for higher intensity
The problem is that many people either run too hard , too easy – or completely forget that Zone 2 still requires energy. The result? Fatigue, lack of progression and loss of quality in the overall workout.
Here's what you need to know to get the most out of your leisurely walks.
Zone 2 is not “free training”
A common misconception is that Zone 2 training is virtually energy-efficient because the intensity is low. It is not.
In Zone 2, the body works primarily aerobically, and you burn relatively more fat than at higher intensities – but you still use both fat and carbohydrates as fuel. And the longer you are out, the greater the total energy expenditure.
If you don't top up along the way, you risk:
- early fatigue
- decreasing watts and higher heart rate
- lower training quality
- longer recovery time afterwards
You may complete the trip, but you won't get the full benefit of it.
Why carbohydrates still play a role
Many people associate fat burning with avoiding carbohydrates. In practice, it is often the opposite that gives the best results.
Carbohydrates help to:
- keep the intensity stable enough that you actually stay in Zone 2
- support muscle work over a longer period of time
- prevent you from “falling through” towards the end of the pass
When the carbohydrate stores are depleted, the watts drop. And when the watts drop, you drop into Zone 1. It still feels calm – but the desired training effect gradually disappears.
Zone 2 is not about riding as lightly as possible, but about lying precisely in the area where the body is optimally stimulated.
How to eat optimally on the Zone 2 trip
The right fueling depends on duration, intensity and your training level. Here are some practical guidelines:
Up to 60 minutes
Water may be sufficient for many.
But a light carbohydrate source like Premium Endurance can provide more stable energy while also ensuring electrolytes – especially if you train early, fasted or for several days in a row.
90–150 minutes
This is where carbohydrates begin to play a clear role.
30–60 g of carbohydrate per hour is a good starting point, for example:
- 1 Noutron Energy Gel C30 per hour
- Premium Endurance in the bottle
It keeps energy levels stable and makes it easier to keep the intensity precise.
150+ minutes
On longer trips, the requirement increases significantly.
60–90 g of carbohydrate per hour is recommended, for example by combining:
- Energy Gels
- Fuel Bar C35
- Premium Endurance
The goal is not to “overfuel”, but to avoid the gradual energy decline that can otherwise ruin the quality of the last few hours.
Know your zones – and don’t blindly copy the pros
A key point in Zone 2 training is that you know where your own zones lie . Heart rate, watts and pace vary enormously from person to person, and Zone 2 is not a fixed number that you can just copy from others.
As we also talk about in one of our recent podcasts, you can't uncritically transfer what the professionals do to your own training. They have:
- many years of systematic training
- extremely high aerobic capacity
- a body that is optimized for high volumes of training and rapid recovery
For most exercisers, Zone 2 requires more awareness, more structure – and often more fueling than you might think.
Use knowledge – but use it correctly
Zone 2 is a powerful tool when used correctly. It's not just "easy training," and it's not an excuse to run without energy.
Know your zones. Fuel your training. And remember that the quality of the easy sessions is at least as important as the intensity of the hard ones.
This is where the foundation is built.
