Why do we use prescribed weights and prescribed movement variations in workouts?
SparkNotes/less winded version:
Having an RX weight and movements with each workout allows our coaches to administer and scale appropriately for the desired stimulus of each workout that is programmed and completed. Thus, allowing everyone to get a similar physiological response from the programmed workout of the day.
For all of our members, having an RX weight and movements with each workout ensures that you are inching towards long term goals and constantly trying to be better than yesterday (avoiding complacency).
Prescribed weights and/or movements also give you a better understanding of how things should feel in each workout you complete and ensures that you have the best workout possible for your current fitness level. A 135lbs deadlift certainly means and feels different than a 275lbs deadlift just like a 30 inch box jump provides a different workout than a 20 inch box jump.
I want to dig deeper and nerd out on all things Rx’d!
RX is a term usually used in medicine meaning ‘prescription’. Applied to CrossFit workouts, we use the term to determine the exact prescription of a workout, and from that the overall intent or stimulus, which can be described as the effect of a workout on our physical and psychological systems.
This is significant in that CrossFit training is not just another high intensity training program, but that each workout is in fact a careful and precise blend of movements designed to elicit a specific response from the body. This makes it necessary to have prescribed movements, loads, and reps i.e ‘RX’ so that we may define exactly what that response should be for each workout we are coaching.
One of the goals of the CrossFit coach is to ensure that every athlete gets the intended stimulus from the workout regardless of their ability level, so we scale movements, loads and reps to preserve that stimulus. The beautiful thing about the CrossFit program is that everyone can do the same workout, tailored to their specific needs, and achieve the same relative effect (stimulus). Allowing anyone, at any age and any fitness level to reap the benefits of doing constantly varied functional movements at relatively high intensity.
It’s also why you don’t have to be super fit to get started at Joust!
When scaling a workout to preserve the intended stimulus, there are a number of factors that a coach must consider, including:
-Range of motion of the movements
-Complexity of the movements
Prescribed weights are nothing you “should do” or “have to do”. Very simply, they give us a long term goal to inch towards while also allowing our coaches to better explain how movements and workouts should feel based on what prescribed weights are suggested for the workout, all with the goal of achieving the desired stimulus of the workout while keeping everyone safe and happy.
Always remember TECHNIQUE-> CONSISTENCY -> INTENSITY.
If range of motion and technique are present, try a little more weight or slightly more difficult movement in a given workout. If range of motion or technique is lost, scale back a bit and avoid moving closer to RX.
Food for Thought
Remember that our goal is to live a more functional life outside of the gym by learning and practicing functional movements inside of the gym. It’s NOT to become a professional CrossFitter or to injure ourselves doing something our body is not ready for in the present moment. Also remember that everyday is different, your body doesn’t care what workout you completed RX’d yesterday.
Wait, what, I need an example?
Here’s a workout example for you:
If a 65/95lbs thruster is prescribed in the workout “Fran”, as coaches we can explain a lot of things about that weight and how it should feel and what the overall stimulus of the workout is.
We can draw from that weight and this rep scheme that 65/95lbs for “Fran” is a weight that will feel moderate and is a weight you ideally should be able to do between 12-15 unbroken repetitions while fresh. It also means your heart rate will be up as well as the intensity level due to the higher repetition sets you’ll be completing, working closer to the anaerobic glycolytic energy system.
Based on that, if we change the prescribed weight for “Fran” to 95/135lbs, we know that will feel heavy and should be a weight we could do 4-6 unbroken repetitions of while fresh. This will also lower the intensity of the workout slightly as you’ll be breaking the repetitions up more frequently which will lower the heart rate slightly. It will also mean that we will be working closer to the anaerobic phosphagen energy system with short, intense bursts of energy and 4-6 repetitions at a time used during the sets of thrusters.
These are two very different workouts working in different energy systems all by changing the prescribed workout weight.
Our coaches also give you a time goal with each workout to dial in the desired stimulus. A 65/95lbs “Fran” would have an overall time domain stimulus between 4-8 minutes with the set of 21 ideally being broken up 2-3 times, the set of 15 broken up 1-2 times and the set of 9 broken up 0-1 times. A 95/135lbs “Fran” would have a longer time goal between 8-12 minutes with the set of 21 ideally being broken 4-5 times, the set of 15 broken up 3-4 times and the set of 9 being broken up 1-2 times, it will feel heavy throughout.
Bringing this full circle:
For a member example of those weights, when example member “Joe” sees 65/95lbs as the Rx’d weight that might mean 75lbs for him because that feels moderate and is a weight he knows he can do between 12-15 unbroken repetitions with while fresh, it doesn’t mean he should automatically do RX’d weight. If he sees 95/135lbs Joe would likely use 95lbs for the workout, maybe even 105lbs if he is feeling great and proper technique and range of motion are preserved. If Joe has done “Fran” a time or two before at 75lbs and achieved the 4-8 minute goal with full range of motion, then he could try 80-85lbs this time around, moving to a new level with his health and fitness!
You can see where an Rx’d weight can really help us dial in the proper stimulus of a workout. We want the majority of members in a class and throughout the day to be within the same ballpark of stimulus for the workout of the day. It isn’t always perfect but it’s much better than just playing a guessing game each workout.
This is also where the workout app Beyond the Whiteboard comes in very very handy and makes tracking your progress super simple.