When I was training for a six week expedition in Patagonia, I was trying to get used to carrying a pack with 50 kilos in it. Carrying the pack uphill was the most beneficial training, but coming back down can really put a huge amount of strain on your knees and won’t really help you and may well cause an injury.

Fill up the required amount of old plastic bottles with water, one litre per kilo, and then carry this uphill for up to a couple of hours. Before coming down you can empty all or some of the water to take the strain off your knees.