Unfortunately, there is no general rule for this question. On the one hand, of course, it depends on how fast you go and how steep the terrain is. Additionally, your physical condition and external influences play a major role. In heat, during winter hiking or in thin mountain air, your body has to work harder and accordingly needs more calories. You've definitely deserved a mouth-watering “Kaiserschmarrn” at one of the countless mountain huts and Alpine pastures in Ötztal, because hiking keeps you healthy and burns almost as many calories as jogging! A little clue: if John Public, who weighs around 70 kilos, hikes uphill for an hour on one of the varied hiking routes in Ötztal he burns around 500 kcal.