How to train for running at altitude: prepare your body for the mountains

The mountains demand more than just mileage

Every runner has their strengths. Some excel on technical descents, some can hold a steady pace for hours, while others manage their race nutrition perfectly. However, when the route reaches high altitudes, everyone faces the same challenge: reduced oxygen.

In events such as the Tenerife Bluetrail by UTMB®, where some categories cross the Teide National Park and climb to over 3,500 metres, altitude becomes a key factor in performance. Preparing to run in these conditions can be the difference between enjoying the experience and simply enduring it.

What happens to the body as altitude increases?

As we climb higher, atmospheric pressure drops and the air contains less oxygen available to the body.

This means that the body has to work harder to transport oxygen to the muscles. As a result, runners commonly experience:

• A higher heart rate.
• Faster breathing.
• An earlier onset of fatigue.
• A reduced ability to maintain higher paces.

This does not necessarily mean the runner is less prepared; it simply means the body needs to adapt to a different environment.

Can you train your body to adapt?

The best way to prepare is to train at altitude whenever possible. However, most runners live near sea level and do not have regular access to this sort of environment.

Even so, there are strategies that can help you be better prepared:

• Gradually increase training volume.
• Prioritise aerobic endurance training.
• Strengthen your legs and core to handle long climbs.
• Include specific hill-climbing sessions.
• Practise pacing to avoid starting too quickly.

A strong, efficient runner will usually adapt better to altitude than one with less physical preparation, even if neither train in the mountains regularly.

The importance of pacing

One of the most common mistakes when running at altitude is trying to maintain the same pace as you would at a lower altitude.

In these conditions, it is far more effective to run by feel than by pace or speed.

Slightly reducing the intensity on the first climbs helps conserve energy for the kilometres that follow and avoid excessive fatigue.

Patience is often one of your best allies in mountain races.

Hydration and fuelling matter even more

Altitude can lead to greater fluid loss through breathing and may increase the risk of dehydration.

That is why it is important to:

• Drink regularly.
• Maintain a regular intake of carbohydrates.
• Do not wait until you feel thirsty or hungry.

A good nutritional strategy helps the body cope better with prolonged exertion.

Always listen to your body

Every runner responds differently to altitude.

Whilst some people hardly notice any changes, others may experience symptoms such as headaches, extreme tiredness or shortness of breath.

If significant discomfort appears, the safest approach is to reduce the intensity and allow the body to continue adapting.

The mountains will always be there to return to.

Preparation begins long before the start line

There is no magic formula for performing at altitude, but there is a powerful combination of training, patience and planning.

Building endurance, strengthening the body, learning to manage effort and respecting adaptation times will help you approach any high-mountain route with greater confidence.

Because when the trail climbs towards the sky, preparation becomes the best training partner of all.