Feet and blisters on the GR20

The context

Your feet are your engine

We train for our lungs and the ascent, and often forget the essential: the feet take every step, day after day, on hard, rugged terrain. A blister badly handled on day two can ruin the next ten — and that's exactly where many people throw in the towel. The good news is that almost everything is decided beforehand, with a few simple habits.

Before you go

Prevention starts weeks ahead

The basic rule: no new shoes at the start in Calenzana. Your shoes should be broken in over several outings, and the right size — count roughly one centimetre of room in front of your longest toe. Too small, they crush the toes on descents; too big, the foot slides and rubs. Both give blisters.

For socks, go for hiking models without prominent seams that wick away moisture — a foot that stews heats up twice as fast. Many seasoned hikers also apply an anti-friction cream (such as Akileine Nok) several days before setting off to prepare the skin, then every morning on any sensitive spots (heels, toes).

The reflex

Never wait until the evening

This is the most important advice on the page, and the one you always regret ignoring. A blister warns you before it appears: it starts with a hot spot, a small area that burns or pinches.

Think too about airing your feet: on longer breaks, take your shoes off, let them breathe, change your socks if they're damp. Your feet will thank you over the long haul.

In the evening at the refuge

Treating a blister, step by step

If the blister is there despite everything, treat it cleanly in the evening so it doesn't get worse overnight:

• Disinfect the area and wash your hands.
• Pierce it at the side with a sterilised needle (flame or disinfectant) to drain the fluid, without tearing off the skin that protects what's underneath.
• Let it breathe in the open air for part of the evening.
• Protect it for walking with a hydrocolloid plaster (such as Compeed) that cushions and limits rubbing the next day. Leave it on until it comes off by itself.

If the skin is already torn or the wound open, clean it, protect it and watch for any sign of infection (spreading redness, heat, rising pain). In the mountains, an infected wound is dealt with quickly or not at all.

In the pack

The little "feet" kit

A few grams that can save your traverse. To slip into the first-aid kit:

Sources

To go further

This advice draws on our experience of the twelve days and on recommendations from recognised sources on foot care in hiking (the FFRandonnée and specialist GR20 guides). Every foot is different: test your combination of shoes + socks + cream on your training outings, well before Corsica.