Your fitness level.
Most healthy people can come on a trek. If you are a regular walker or active person you ‘ll be fine. Eighty year olds trek. Obviously it’s better to have UK hill walking experience in, say, the Lake District or Snowdonia and it’s important to realise that you’ll be walking between 3 and 7 hours a day – every day. There are plenty of rests though. If you can comfortably walk carrying a small rucsac for 5 hours on both Saturday and Sunday and not be too tired afterwards it’s OK.
It does pay to do some training, walking uphill is good! So is cycling and going to the gym. Concentrate on leg, knee and core strength. Bending the knees into a squat position and rise without aid is a good idea as most loo’s are squat type so you’ll have do that and not overbalance! Join the Ramblers and walk with them.
You do not have to be super fit or fast! In fact slow and steady is better as fast walkers ascend too quickly therefore are more prone to altitude sickness. It may come as a surprise when an older and slower trekker passes you as you gasp for air. Plodders win out. Having said that the fitter and stronger you are the easier the first few days will be.
It’s important to have good knee strength as they take a pounding but trekking poles really help take some of the strain. We recommend Pacer Poles, designed by a physiotherapist and made in the UK.