I'm really trying to hit the climbing legs this year, utilizing the gym provided stair machine. I'm figuring for margin, where my upcoming trips allow me to not push to the max and get totally trashed out on a hard day. Margin is working my legs to the point where I can climb (in the gym) steadily over hours and keep my heartbeat below 120 BPM, a pace that I can continue through most of a day. When I started this in January I was able to put in 2000 feet per hour. I skipped February but my log indicates that I can now sustain 2400 feet per hour. I am not wearing a pack, so this is not a rate that is equal to hiking trails, which have many more variables, and off trail is also a whole different animal. But getting the legs used to constant stepping should help tremendously. Over the past two weeks I have climbed 20,000 feet over 8.5 hours. Today I put in 4600 feet with a 33 minute 4 mile run thrown in the middle. April is Vert month and I hope to continue to slam the legs without much break, easing off in May. I know a gym is not ideal, I am not getting in any downhill training. However, the ease of access allows me to be extremely efficient in both time management (5 minute drive) and targeting. The ultimate goal?.....motoring all day for up to 15 hours, climbing (on trail) over 8,000 vertical feet and having enough left over for a good night's sleep and be able to do it again the next day.