Most people who have an average level of fitness will be able to survive a trekking adventure, however there is a big difference between surviving the trip and being comfortable and enjoying it.
Preparing for your trek You should start your fitness training at least 4 months before your departure with a focus on key muscle groups: core, lower back, glutes, quads and hamstrings. Coming down is a lot harder on the knees so put some focus on the muscles that support your knees.