[Scott Johnston]

Assaf:  That’s great news that you figured the ME out.  You may have seen a YT video of me doing this workout years ago.  https://www.youtube.com/watch?v=ZI-_rcWcwiY  You can clearly see that I am not going at a sprint effort.  You might also have seen on our IG recently a Tuesday Training Tip by coach Seth Keena a short video of him doing this same workout. It is also very clear that he is not moving very fast.

With regard to the stair machine: Here is my understanding.

If work is force x distance the mass is moved, then the work done against gravity (energy expended) on the stair machine is a function of the distance your mass is raised.  Your mass is not raised by the full height of each step when on a stair machine because as you step up, the step falls away beneath you.  If your mass was raised to the full height of each step, you would quickly hike right off the top of the machine.  It would seem to me that the frame of reference must include the earth and its gravity since that is what you are working against.  With each step, your mass is oscillating up and then back down in relation to the center of the earth but not by the full step height.  This is not the same as when running on a train, where the frame of reference does not need to include the earth because the runner is not working to overcome gravity.

IMO: The reason for high RPE on a stair machine, which gives the impression that this is just as hard if not harder than hiking steeply uphill, is that the gradient is something close to 100%, which is much steeper than almost any terrain you could hike on outside, combined with the step size being significantly greater than the step hight on, say a 30% grade.

But I am happy to hear a rebuttal to my argument.

Scott