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What Does “Rx” Mean?

Well, at Foundry – “Rx’ing” a workout generally means the weights and reps I “prescribe” for a desired outcome.

But before I further define it, please know it is okay and expected that many of our members do not perform the WODs Rx! We pride ourselves on being a gym for EVERYONE, which will require modifications and THAT’S OKAY! For those of you who are able, it is something you should shoot for or work towards. If you’re ever unsure what weight to use, our experienced coaches are equipped to make suggestions that will ensure you get the same stimulus from a workout and are there to make sure you’re putting in your best effort!

In order to Rx a workout we need 3 things:

1 The prescribed weight

2 The prescribed reps

3 Proper movement standards (sorry guys – banded pullups, knee pushups, and partial ROM squats aren’t going to put you in this category)

We then want to look at the desired outcome of each workout.


If the workout is supposed to be short and fast, then when you modify your workout, you should modify it in a way so that the workout is still short and fast.

If the workout is long and slow: then when you modify and scale the workout, you want to scale it so that the stimulus, your intensity, is still long and slow.

The common pitfalls are workouts that are designed to be pretty slow, long, and then someone modifies it, they’re like – “Well, I got it done in like six minutes, man, I don’t see what the big deal was?!”.

By doing that, you’ve missed the intensity piece. 

When we’re scaling movements, there are ways that we can do it. For example, we can scale it by changing the range of motion (pretty straight forward) and we can change the actual movement from a run to a row, but there’s a way to do it.

I define intensity as exactly equal to average power (force x distance / time). And this just turns into this mathematical equation that gives us quantifiable results. Everything that we want to scale for intensity is found in that mathematical equation. So, yes there is a method to my madness!

How To Scale

You can scale multiple components of a workout to make it appropriate for you. The obvious (and probably most prevalent scale) scale is load. I often prescribe a certain weight for a given movement (again, to apply a certain stimulus). This doesn’t mean you HAVE to do the weight so here’s what I suggest if you need to modify your load: look at it on a scale. If I prescribe a 35# dumbbell for DB snatches, are you 50% of my Rx? Are you 60% of my Rx? Think of it that way next time you want to grab a 17.5# dumbbell. Then when you’re passing people who are going heavier than you, you know it’s time to try the next size up.

You can also scale volume. For example, many of you struggle with pullups. If the workout calls for 15 pullups and you really want to get better at them, I suggest you do 12 reps rather than modifying to a renegade row or adding 15 bands. Another one is running – many of you will sub the bike over a run if given the choice. If you have an injury, that’s one thing but for the rest of you, if you need to scale the run to put more effort into it and not drag out a 15min metcon over 20mins, then do it!


The whole point of this email was to provide a clearer picture of whether you should scale or Rx a workout. If going Rx (or vice versa) causes you to completely lose the intensity that was supposed to be in that workout, then you should scale to maintain the intensity. Intensity is the primary thing we’re focused on and the driving force that gets us what we want. The right intensity is how we get our results.

If you are someone who wants to Rx more workouts, maybe it’s time to schedule a consult with one of our coaches. Email us at to schedule.

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