So I live in North Dakota and I'm training for Rainier in April. The old saying about "train to climb by climbing" doesn't work here as we don't have any climbing opportunities. So I've been humping up our state capitol building with a light backpack. I started out doing 36 flights and I'm now up to 54 flights in about 20 minutes. I do about 3x/week with other light weight training/cardio mixed in.
Are there any reasons why I shouldn't be relying so heavily on stair climbing in my training regimen? I haven't noticed any bad vibes from my body, even though I have had a minor knee sprain. As for amping it up, should I add more weight to my pack or just keep it light and do more flights?
Any other advice for training ideas not requiring close access to mountains? Thanks!!