Hi Helen,
The best training is stairs, and stax of them. 30 min – 1 hours, 3-5 times a week. The best type are similar to a high rise building in the cities. (7-10 floors)
You can also do a long walk on the weekend with your pack 10-15km.
Most of the track is up and down, up and down and gain up and down until Owers Corner.
enjoy