The actual day to day trekking is not difficult but it is very rocky and also at high altitude. From intermediate camp you need to ascend up the side of an icy ridge where crampons are advised at the best of times. It does not involve technical climbing, but does require physical fitness and stamina and most importantly, mental fitness. A good exercise and training program is essential and your training should include a lot of hill walking. The higher you climb, the harder the trek will become due to the altitude.