How to train for long walks (~100km)?

Question

How to train to be able to do really long walks (about 100km)?

Is the training for such walks similar to training for long runs? The distance is similar but when walk you can take pauses.

My goal is to be able to take part in orienteering competitions on 100km distance, where I have time limit of 24h. I'm also impressed by student mountain guide training, with include 100km long walk in mountains in winter condition with backpack.

My record as for yet is 50km walk in summer condition with light backpack, but I was sleeping very long next day, and as general, when I walk more that 20km I have often headache, so I think it can be lowered sugar level, which means for my body it's a 'calory shock'.

How to prepare my organism for such big effort and calory usages? Is it possible, that only some people are able to such effort and I will stop on this 50km border?

Answer 1

To keep going for long time periods, you need to stay hydrated and to take in calories, primarily in the form of carbohydrate, and salt, to replace what you have sweated out. You can generally absorb somewhere around 250-350 calories per hour while you are exercising, and if you are working hard, you can sweat a liter an hour, or more if it is hot.

I suspect dehydration as the source of your headache, though if you are up high (say, 2500m or higher), you can also get headache from altitude sickness.

If the latter is the case go down to lower heights as soon as possible, after you start feeling the headache.