What is Smart Sets?
Smart Sets™ is a feature of Cortex®, Volt’s proprietary AI system, that uses subjective feedback to regulate the intensity of a training session. Smart Sets helps ensure your training prescription is hyper-personalized to how you are feeling on any given day—to make sure you continue progressing, while avoiding overtraining and injury.
When Smart Sets is enabled on your program, Cortex will ask you “How hard was that set?” after sets of loaded (non-bodyweight) movements. Based on your answer, in the form of a 1 to 10 Rating of Perceived Effort (RPE), Cortex may adjust your estimated 1-rep maximum (e1RM) for that movement—which then adjusts your weight recommendation for your next set. This method of “auto-regulation,” by which you (the user) are regulating your training session based on your own perceived effort, is a proven and effective method of strength progression.
How does it work?
To make adjustments to your e1RM, Cortex compares how hard you felt the set was to how hard we would expect that set to feel for you. In other words, Cortex compares your actual RPE to your expected RPE. So, how does Cortex determine your expected RPE?
To determine your expected RPE, Cortex references research on relative intensity (originally done by Soviet strength coach Alexander Prilepin). Relative intensity refers to the percentage of an individual’s maximum effort or capacity that is being used during an exercise. Prilepin’s research linked the concept of relative intensity with absolute intensities, which can help strength coaches prescribe loading and rep schemes that are individualized to each user.
For example—a set with a relative intensity of 100% (max difficulty) can be correlated to the following loading and rep schemes:
- 100.0% x 1 rep
- 95.0% x 2 reps
- 92.5% x 3 reps
- 90.0% x 4 reps
- 87.5% x 5 reps
- Etc.
Let’s say you have a Barbell Back Squat with a estimated 1-rep maximum of 100 lb. If you perform 1 rep x 100 lb or 5 reps x 87.5 lb, both sets have a relative intensity of 100%. The following chart shows a breakdown of this concept:
If a strength coach wants to prescribe a set that is a relative intensity of Heavy, according to Prilepin’s chart, they could prescribe 1 rep x 92.5% or 10 reps x 67.3%, depending on your specific goals. Both sets would feel relatively Heavy for you.
Cortex takes relative intensity one step further by correlating it to RPE ratings. Cortex uses a 7-point RPE scale to collect feedback after each set.
- 10 — Max Effort
- 9 — Very Hard
- 8 — Hard
- 7 — Somewhat Hard
- 6 — Medium
- 5 — Easy
- 1-4 — Very Easy
When you provide an RPE rating, Cortex compares the actual loading x reps you performed with the RPE rating we’d expect for that set based on Prilepin’s relative intensity chart. If the RPE rating is aligned with the relative intensity we’d expect, Cortex will not make any adjustments to your estimated 1-rep maximum for that movement. For example, if you lift 80.0% for 1 rep—which we would expect to be “Moderate” based on Prilepin’s chart—and you provide an RPE rating of 6 (Medium), Cortex doesn’t need to adjust your estimated max because you’re right on track.
However, if the RPE you provide is much greater or lower than what we’d expect, that’s when Cortex will intervene. Let’s say you lifted 80.0% for 1 rep, but instead of RPE 6 you say it was an RPE 8 (Hard). That’s 2 RPE ratings greater than what we would expect for you, based on your current estimated max. At this point, Cortex will make a slight adjustment to your estimated max in order to keep you working at the proper relative intensity, or expected RPE. This method helps athletes continue to progress and challenge themselves while avoiding injury and overtraining.
What if I don’t feel like Cortex is working?
While Smart Sets works well with many different styles of training and types of movements, it is generally most accurate when you are lifting heavier loads for fewer reps. That’s because it’s easier for you to be precise about your RPE when you’re working closer to your actual 1-rep maximum. If you are lifting 50.0% of your max for many reps, it’s generally harder to provide a precise RPE rating. Let’s say you lifted 58.0% x 8 reps (”Light” on Prilepin’s chart) and give an RPE of 5 (Easy). Based on your relative intensity, we’d expect that set to be RPE 1-4 (Very Easy). But the distinction between Easy and Very Easy can be difficult to discern as the lifter.
If you feel Cortex isn’t adjusting your maxes as you would expect, it’s possible you’re not lifting a heavy enough load, or for enough reps, to allow for a precise enough RPE. An easy way to “fix” or “recalibrate” is to perform more reps at the prescribed weight. If you lift 70.0% x 1 rep, we’d expect that to be RPE 1-4 (Very Easy)—but if you lift it for 8 reps, we’d expect it to be RPE 7 (Somewhat Hard). If you tell us 70.0% x 8 reps is RPE 5, Cortex will adjust your estimated 1-rep maximum to be higher.