[Felipe Q]

I have been working through the time crunched mountaineering training plan and have come to the longer aerobic pace hike/workouts. This involves sustaining heart rate in a prescribed zone for the entire length of the activity. Due to living in the flat lands, I have two options for this training, a stair mill machine in the gym which has a rolling staircase that you have to step up on, and real stairs which require ascending to the top of the building, about 250 feet, and then riding the elevator down and repeating.

You have mentioned previously that real stairs are preferable to a stair machine due to the stairs falling away from you and reducing the effort required. I do notice that my sustainable pace on a stair machine is noticeably higher than when climbing real stairs which supports the fact that climbing real stairs is harder than riding a stair machine. The down side to using real stairs is the requirement to stop at the top after a 7-8 minute ascent, and then travel back down to the bottom for 2-3 minutes while my HR drops back down into the recovery zone.

For a workout which requires a steady HR to be maintained for an extended period of time, my inclination is to do this on a machine which allows for an uninterrupted ascent and a steady HR for the prescribed period. I’m not sure though if the harder effort on real stairs may be preferable to machines in all types of workouts. There are “interval” type workouts built into the plan which require sustained work for a short period followed by rest periods in between. These lend themselves nicely to a real stair workout. Any guidance from the community would be appreciated.

Topic

[evan.piche]

evan.piche on May 8, 2019 at 6:15 pm #21728

My girlfriend (not a climber) thinks I’m crazy for thinking about this shit. Thanks to everyone who contributed to this thread for making me feel less weird.

[Adam Fern]

Adam Fern on May 15, 2019 at 2:25 pm #22055

@vencislav.popov and @johnepearson

With respect to your cited articles (thank you for linking those, btw) and Ph.D, I disagree that effective vertical gain on a stair mill is the same as real stairs (or hill) outside. I also disagree that the work done is relative to the stairs, not the earth. Granted, a large part of expended effort is just from mechanics of turning your legs over, but in terms of a purely physics perspective, stair mills are less “efficient” for racking up vert.

Work can be defined as a change in total energy, e.g. increasing potential energy by traveling uphill. If I climb 1000 meters up a hill, I have increased my potential energy by a factor of 1000 (m*g*1000 – m*g*0). In other words, my CG, my body, etc, has moved away from the center of the earth. On a stair mill (I’ve done a rough calculation at my own gym), in the time it takes me to take one 9″ step, the stair moves about 5″ down so my CG (measured at my chest) is raised 4″ with each step. (The remaining stair/body travel happens during the dead time when both feet are on the steps traveling downward.) To expand on this example, if I took 1000 9″ steps outside, I will have moved my CG 750′ away from the center of earth. Taking 1000 9″ steps on the stair mill equates to an equivalent CG gain of only 333′.

As we all know, metabolic inefficiencies and human mechanics make this whole discussion quite contrived, and the actual physical work done represents a small amount of total (including chemical i.e. metabolic) energy expenditure.

Love the discussion!
Adam

[Adam Fern]

Adam Fern on May 15, 2019 at 2:59 pm #22060

@vencislav.popov and @johnepearson

As I reread your posts and think about this more, I see the point you’re making. The reference frame of a stairmill/treadmill is moving, but it’s still Newtonian, i.e. not accelerating. Perhaps the argument I’m making would apply only if the stairs were accelerating away from you, rather than moving at a constant rate.

The realization I had was by thinking about doing squats (just for example) in an elevator traveling down at a fixed speed. The amount of work I do, or the change in my CG w.r.t. to floor of the elevator is still positive, despite the elevator’s downward movement.

Thanks for the alternate perspective. As a purist, I still don’t know if I’ll count vert on a stairmill as real vert, though! 🙂