Definition of set of step ups/downs?

I'm looking for clarification on this 12 week training program: http://www.fitclimb.com/page/12-week-mountaineering-fitness

Can someone tell me what exactly a set of step ups means? Is a set of 40 step ups 20 right foot first and 20 left foot first, or 40 of each? How about for step ups left/right and step downs? 

Thanks for your input.

I've always done one step up right, and then one left, and would count the set as the total of right and left. Seemed like the best way to mimic actually walking up a mountain. Otoh, you might get more stimulus from doing all one side and then all the other as fatigue accumulates.... But that's really getting into the weeds.

I think the real answer is to do what feels good and natural to you. Presumably the fact that you are asking about this program means you are coming off the couch - or at least out of a non-sport-specific training period. In which case, pretty much any amount of specific training will vastly increase your capacity, and you can really play it by ear based on your schedule and recovery capacity and get about the same results as doing any other reasonably designed sport specific training program.

Otoh, if you're the next Steve House and are already highly trained and are hoping this program will boost your fitness to the next level so you can send your uber-proj that will get you sponsorships from Patagucci and The South Butte - but only if you do it exactly as written - then hopefully you have the clout and connections to get in touch with the programs author and ask them for a more detailed explanation.

Thanks for the 2 cents Brice. You nailed it - I'm coming off the couch after some life changes and looking to train for better all around fitness this time around as well as for some moderate alpine objectives.

With the number of reps you have in that plan (40), it looks like the goal is to get that burn/exhaustion in the muscle, and the cardio rate up.

So I would try doing 40 step-ups on the left, then 40 step-up’s on the right. The way they have it worded for the side step-ups makes me think that this is what they mean.

But when I personally do step-up’s as part of my warmup before climbing, I alternate feet. It makes for a slightly weird hop at the bottom, bc I step up/down with the right, switch foot, step up/down with the left, switch foot, etc. (I just do one of those tabada-style 30sec on/10 sec off 8 min workout thingies, and my goal is to warmup, to to get exhausted, lol).  

In exercises like these I consider step left/step right to be a set of 1. So either way, whether you are alternating or repeating the same side, you will have a total of 40 on each side.