What does Rx mean?
Originally, Rx meant ‘prescription’. CrossFit borrowed that meaning and began using the term Rx to notate when a workout was “as prescribed” rather than modified or scaled.
In CrossFit, daily workouts (WODs) are written by the head programming coach and each exercise has a specific weight, reps and performance points that go along with it. Rx or ‘as prescribed’ refers to the workout exactly as the coach wrote it.
When a workout is written and posted, the head coach will specify descriptive points (such as weight, distance, etc) that indicate the “Rx” version of the workout.
Most often, the Rx versions will be different for males and females – males often have a heavier weight, higher box height and sometimes longer distance to row or bike.
Typically, these Rx specifications are written next to the exercise or underneath the exercise, but they should always accompany the workout.
For example, a workout is usually written like this:
AMRAP 10 Minutes 10 Box Jumps 24”/20” 10 Push Presses 95/65# 10 Toes-2-Bar
To complete this workout Rx, a male would have to use a 24” box, a 95# bar and perform toes-2-bar. A female would use a 20” box, a 65# bar and perform toes-2-bar to complete it Rx.
Rx versus Scaled
If a member cannot do the Rx version of the workout, they will do a scaled (modified) version. Exercises can be scaled in a number of ways – the most obvious is that the Rx weight would be lowered.
An exercise could also be scaled by decreasing the repetitions, decreasing the height of a box jump/step up, adding assistance to pull-ups, handstand push-ups and/or dips, decreasing the length of a run, bike or row, etc. Scales are typically determined by the coach and/or member.
In the example above, a male could scale the workout by using a 20” box, using a bar less than 95# and/or performing knees-to elbows instead of toes to bar. A female could scale the workout by using a 16” box, using a bar less than 65# and/or performing knees-to elbows instead of toes to bar.
Rx vs Scaled Scores
It is important to note that if even one exercise is performed scaled, it makes that entire workout scaled. In order for someone to say they did a workout Rx, the member must do all of the exercises as prescribed.
Sometimes, a member’s fitness level is such that he/she can do some exercises as prescribed (Rx) and others scaled.
In this case, when writing scores on the whiteboard, it is typical to only include details for the exercise(s) that were scaled, and it is assumed that the others were performed Rx.
Using the example above again, scores for this workout could look like this:
Rx Athlete – performed the workout Rx:
5 rounds + 6 box jumps Rx
Scaled male athlete – scaled one exercise (used 75# instead of #95)
4 rounds + 2 Push Presses, 75#
Scaled female athlete – scaled all exercises (used 16″ box instead of 20″, used 55# instead of 65#, did knees-2-elbows instead of toes-2-bar)
4 rounds + 3 box jumps, 16”, 55#, knees-2-elbows
Note that writing Rx on the board is an achievement to strive for and something many athletes are proud to train hard to accomplish.
How is Rx determined
A few factors are considered when a coach writes a workout and determines the Rx weights and standards. First, he/she decides the metabolic goal of the workout. If the goal is for strength, the Rx weights will be heavier.
If the goal is metabolic conditioning, the Rx weights will be lighter so the athletes can move faster. Second, a coach should consider his/her community’s fitness level.
An Rx workout to a brand new group of CrossFitters might look different than an Rx workout for a group of athletes training for competition.
Typical Rx Weights
Some common exercises have weights typically associated with Rx for workouts. A coach can program any weights they choose for their gym’s WODs, but these are used often in WODs across the global CrossFit community:
- Cleans: 135/95#
- Snatches: 95/65#
- Thrusters: 95/65#
- Dumbbell Snatches: 50/35#
- Kettlebells: 2 pood/1.5 pood
- Box Jumps: 24”/20”
Additional uses of Rx
Within the crossfit community, the term Rx is also used to notate an athlete’s ability. An “Rx athlete” is someone who is able to perform the Rx version of most if not all movements and workouts.