Stair climbing with weight is one of the best training activities you can do to prepare for a mountain climb.
What you need: a good pair of shoes or boots, a pack and a long flight of stairs. Do an internet search of Stairs Workouts and the name of your city for some ideas of urban stairs people use for training. Here in Seattle, favorite stairs used for training can be found at Howe Street and Blaine Street Stairs, Capitol Hill-Eastlake, Thornton Creek Water Channel Stairs, Highlands Issaquah, Volunteer Park, Wilcox Wall, and Golden Gardens Park. If you work in a building with flights of stairs, use those for your training. You can also use a Stairmaster cardio machine.
Start moderately and progressively increase the length of your stair workouts. Monitor your body during and the days after your stair training for signs that you overdid it and back off if you did.
If you are just beginning your training, walk the stairs without weight for 20 minutes. If you are fit, and have been doing some stair climbing, start with a light pack and gradually increase the duration of your workouts and the weight with your subsequent workouts. Over time, work up to the weight that you will carry in the mountains.
Go up the stairs, going slowly for the first five minutes to warm up your body. Then pick up the pace a bit. Once you have been training stairs for a few weeks you can also try Intervals. One interval protocol is 30 seconds of hard activity followed by 60 seconds of slower activity. Tabata Protocol is another, more difficult interval program that combines 20 seconds of activity with only 10 seconds of rest. Go fast for 20 seconds and then go slowly for 10 seconds.
Once you get to the top, walk down the stairs. Go slowly as you descend. If you are training in a building, take the elevator down stairs. Going down stairs can be hard on your body. So be careful not to overdo it. Extremely repetitive stair climbing can put your knees, at risk for overuse injuries.
Once you are done, walk slowly for five minutes to let your heart rate cool down, stretch and hydrate.