You’ll need a reasonable level of fitness to hike the Inca Trail. Although the trail itself is not too challenging, and you can hire porters to carry your bag, the altitude makes the hike feel tougher than it would at sea level.
The most popular route covers 43 km (27 miles) over four days, and you can expect to be walking for about six hours each day. If you exercise regularly or are a regular walker and leave yourself a few days to acclimatize before attempting the hike, you should be fine on the trail.