GR20 revisited

Like in 2012 I started south in Conca and ended north in Calinzana. Unlike 2012 I finished! It took me 11 days. I never came close to my physical limits.

In this article I would like to describe the preparations and the execution of the planned tour.

Hiking direction

I decided to go from south to north.


  • Acclimatisation. The south is a bit easier and not as high. I have not trained in 2000m a. s. l. Need to adapt to this first.
  • Like a long distance run. The best part comes last, not first.
  • Increasingly fit. With all the training in the south I can enjoy the north much more.
  • Security. I am alone. Many hikers follow the north to south recommendation. They walk towards me.

How to do it

From the previous GR20 experiences I planned like this:

  • I planned for doubling stages and recovery stages. Recovery stages are meant to be easy and quick. The rest of the day should be used to recover, i.e., lying around, sleeping, talk to others, eat, just do nothing. Double stages are more challenging.
  • My back pack has to be as light as possible, optimally not exceeding 10kg.
  • My water and food supplies have to be plenty to never be thirsty or hungry when walking from réfuge to réfuge.
  • I walk. I do not run. And I certainly do not sleep/dream during walking.
  • I have to be fast enough to arrive at the next réfuge within +/- 4 hours.
  • I avoid blisters.



  • Physical training.
  • Testing the material for endurance and compatibility to my body during physical training.
  • Testing the food for tolerability and effect during physical training.
  • Avoiding blisters
  • Testing all of the above three months prior to GR20 on a training trail.

Physical Training

Stamina: Twice a week 24km walk/run with 600 meters of height difference (600m up, 600m down) on gravel road with a 11-13kg back pack. Gravel road represents best the GR20 terrain. The limits are 4h 30min when walking at an average heart rate of ~100/min and 3h 15min when double-timing at an average heart rate of ~130/min, the lower the better in both cases. After training you should never feel exhausted no matter the temperature or heat. Temperature may vary from 10°C to 30°C, much like GR20.
Because repeating the same training trail over and over again training may become boring quickly. No matter how tempting do not only run. 50% of your training you have to walk. Walking is different from running in many respects, especially with a back pack. Walking is where you get blisters from. Blisters usually do not come from running. In training you either fully walk the whole training walk or your mix between running and walking. When exercising the latter run where terrain flat or sloped. Walk where you have to ascent. Measure your burnt calories count in every training. This will give you an indication how expensive which form of movement is and helps determine the amount of food you have to carry.

Workout: Twice, sometimes 3x a week: focus on gluteus, hem strings, tighs (vastus medialis, rectus femoris), hips (), abdominal muscles and their counterpart on the back. The thighs are extremely important due to walking up and down a lot. The hips are important for walking long distances without pain in the hips. The torso will carry the back pack hence the sit-ups and the workout of the back.


Put an imperative on socks and shoes. Avoid blisters at almost any cost. My best experience is with trail running shoes and thick Icebreaker Merino wool hiking socks. While the shoes should be used well the socks should not be old and worn out.
The back pack should be able to carry the intended weight with all the items required on the GR20 in a way that is agreeable for the wearer. It should be durable and light and if possible more or less waterproof. All this is best tested during training. Later, on GR20 you will use the same shoes and socks you used for training. Do not buy new stuff!

Choose the rest of the material wisely. The more you pack the heavier you carry. If unsure with an item test it during training.


Water. The more water you have to carry the harder the walk. Try to optimize the weight of the carried water by defining your consumption. This can be measured. Instead of a water bottle use a drinking system, i.e. a camel back. Take a sip, spit it out into a measuring cup. Implement a drinking rhythm en route, i.e., every half hour 4 sips. Check out how you feel with this rhythm when being in different thermal environments. If not OK change the rhythm to longer or shorter intervals. The important thing is never to be thirsty. When you become thirsty it is too late. Sooner or later you will fall into a performance trap.
This method will determine your overall water consumption and thus how much water you must carry to cover a certain amount of hours of walking. For me a 1.5 litre camel back was always enough to walk from one GR20 stage, meaning from hut to hut, 3-4 hours per stage.

Liquid food / isotonic water. Depending on the length of your daily walking and outside temperatures water only may be sufficient. However, do not count on this. The prudent way is to enrich your water with isotonic powder. I use Sponser Competition. I packed 1.6kg for the whole GR20 to find out that 1.2kg would have done the job. Sponser Competition does not just make water isotonic it also makes it liquid food.

Solid food. Same as with water applies. Eating rhythm is as essential as drinking rhythm. The idea is never to be hungry. My eating habit was first breakfast, followed by 1 high energy bar after 2 hours of walking, followed by a hefty meal after another 2 hours of walking, followed by 1 high energy bar after another 2 hours of walking, followed by another big meal after 2 hours of walking. The latter big meal never came to existence. This 2-2-2 rhythm was fine for me and well tested during training. However, if i.e. the breakfast was not as big as required I either added one high energy bar to the breakfast or had the first high energy bar already after 1 hour of walking. I listened to my body. I did not allow myself being hungry.
Choose food according to these parameters: 1. tolerability, 2. amount of Kcal per weight unit (ie. grams), the more the better, 3. overall size, the smaller the better, and 4. taste. If it does not taste well do not use it. Do not use food that is large in size, has a low calories count and above all is heavy. Apples are a bad example.

Tolerability of food

Because of food you should not have more flatulences and burbs than one would usually have. If this is the case there may be an intolerance and you might want to test other food. It is worthwhile to test this during training. If food works OK it will not unnecessarily make you feel uncomfortable and thus drop your spirits.
I drank Sponser Competition isotonic powder and ate Sponser High Energy bars. En route for the big meals I ate what the huts cooked or sold. I never had problems.

Avoiding blisters & sprained ankles

Blisters and bloody feet are a result of insufficient preparation and/or a bad distance dosage. Training walks are also there to test your socks and shoes and prepare your skin for a more intense life. If during training you never got blisters you should not get blisters on the GR20. Stay within your trained limits or, if you overextend, do it by a little, not by a lot. If your training walks were around 25km then your GR20 stage should probably not be like 40km. Instead, if you overextend, aim for 28 or 30km.
If you get blisters during training it is because of your skin that is not used to walking or your shoes or your socks or a combination of all reasons. This is where training walks help you to find out about yourself.
If nothing helps you can help avoiding blisters by taping. During training you will find the places where blisters occur. Tape before you get a blister, not after. Blisters usually announce themselves as skin getting hot like burning on a certain spot. This is the time to stop and fix those spots with tape to reduce friction. When fixed you should feel normal immediately. Be careful and precise when applying the tape. There must not be any folds. If applied carelessly problems are certain!

On the GR20 you will always meet somebody with a sprained ankle. This usually happens when people dream walk: They "fall asleep" and do not anymore pay attention to the ground they walk on.
Never ever dream walk! Not for one second! If you want to enjoy the country and the beautiful views of which there are plenty, stop. Do not walk. Stop and enjoy. If you are tired, stop.
When walking, however, do pay attention to the path in front of you.
And no, opposite to common believe, ankle-high boots do not prevent sprained ankles!

Test everything

For the past few months you have done a lot of training, workout, testing food and material. Now it is time to put everything to the big test three months prior to GR20. Find yourself a trail you want to walk in 5 or 6 days. Take your equipment and walk it and see how well things work out.
I chose the GR221 on Mallorca with 6 days of walking. This trail is 120km and about 6000m height difference. The trail is easy to walk and fully sufficient put everything to the test. This will show you where you are strong and where you lack. Use the coming 3 months before departing for the GR20 to optimize your training.

Walking the way

Details of every stage are available by enlarging the google maps window and clicking on every item on the map, including my path (in blue).


Total marching time57.06h
Blister count0
Orangina & Coca Cola cans drunkuncounted
Bad GR20 dinners eaten *)7
Good GR20 dinners eaten **)2
Problems with stomach0
Bed bug bites>30

*) Paliri, Usciolu, Col de Verde, de l'Onda, Manganu, Di I Mori, Carozzu

**) Matalza, Hotel Monte D'Oro

In terms of food there is one thing important to remember. There is no such thing as bad tasting food on the GR20. Long hours of walking lead to quite a hunger at the end of the day. You eat whatever they sell you. This doesn't necessarily mean that you would eat the same food at home under normal conditions.