Set level data is where the rubber hits the road. The question that actually matters in VBT is “what do these set numbers tell me?”
Knowing where to focus attention when reviewing a set is the most important step in using velocity to autoregulate training and track progress.
At the end of each set, your velocity tracking system (MetricVBT is my favourite 😉) will spit out a rep-by-rep breakdown, usually in table and bar chart format. In the MetricVBT app, you also get a set summary dashboard that gives you an instantly glanceable overview of the most important numbers in one place.
Common issues when tracking bar speed in the gym
Before we start crunching the numbers when reviewing a set it’s important to be aware of three common variables that can impact a set.
Applying intent to move
The first thing to consider before even looking at the velocity data is to determine if good intent was applied to each rep of the set.
Intent is effectively a measure of effort, and is the difference between trying to perform fast reps versus deliberately slow reps. The simple question when applying intent is did you try to lift each rep as explosively as you could for that weight, the bar speed doesn't have to be blisteringly fast in absolute terms, it just has to be a maximum (or near maximum) request from your nervous system to move as fast as you can for that given movement.
Intent is a key part of driving training adaptations and you should be applying great intent whether you track velocity or not, once intent is consistently applied at a high level, then we can begin to make assessments of performance and readiness from our velocity data.
Working phase velocity is ideal
Given what we explored in part two: Analysing a rep, I will be referring to work phase velocity from here on, however, the same rules apply for mean or peak velocity metrics. These principles and examples will also work when using power metrics. For simplicity I will just use the cover-all term velocity.
Don't forget to review each set within it's context
This blog post will focus on a single training set in isolation, but it’s important to keep in mind that most of the value to be gained when training with velocity is in comparing your sets from today's session with the numbers achieved in your recent history. Whether it's velocity, range of motion, power, tempo or something else entirely, it's these relative scores that give context to how well you are tracking in the short and long term.
We will tackle how to use this contextual data in a later part but for today we will focus on the data available from a single set.
With these three points out of the way, let's break the set down.
Best rep velocity/power
In the MetricVBT app velocity data is shown in a table and bar chart format like so:
The fastest rep is usual the first or second rep in a set, when fatigue is at its lowest. Mis-grooves or a lack of tension on the first rep are common so a little increase on the second rep is normal.
This single fastest rep is where I focus most of my attention after each set.
Because speed and power are more sensitive to fatigue than strength, the best rep is the great way to gain an indication of your readiness to train, motivation to lift, how much intent to move was applied, or if the effects that underlying fatigue might be impacting the session.
If the best rep occurs later in a set (beyond say the third rep) there probably wasn't enough intent applied at the start of the set and the lifter is likely going through the motions. In some contexts this is normal and expected (high volume training) but if intent is desired, this is a great opportunity to encourage more effort on every rep, making this a great objective motivational tool!
Set average velocity/power
Average velocity combines the velocity of every rep across the set into a single averaged value.
Set average can be insightful where an athlete is consistently performing the same number of reps on all sets, say during a 5x5 programming block. Using the set average on this 5x5 program might be of interest to monitor progress, however the same thing can be achieved with best rep velocity instead. The added benefit of the best rep method is that the historical data remains relevant when the program changes to a 3x3 block for example.
Because this average velocity is tied directly to the rep count it is highly variable, making it tricky to extract any meaningful information about readiness or progression across training blocks.
I rarely use the set average when training or programming.
Velocity loss / percentage fatigue
The fastest rep of a set (best rep) provides information about intent and fatigue levels compared to recent sessions. Velocity loss is a great companion metric for best rep velocity as it highlights the proximity to failure on a set. This is called exertion, or how much of a grind the set was.
Velocity loss is calculated as the percentage decrement in velocity between the fastest rep of the set and the final repetition of the set.
A high velocity loss is linked to having a greater RPE and therefore less reps left in the tank. The exact values can vary by number of reps and for individuals. Generally speaking, a velocity loss of 40% matches to an RPE-9 / RPE-10, while 20-25% is more typical of RPE-7 / RPE-8 level exertion.
You can use velocity loss in conjunction with RPE/RIR to autoregulate the reps completed in real-time by setting a velocity loss stop-point for each set, something we will explore in a later part of the fundamentals series.
Velocity loss does have it’s limits however and is only really effective for sets within the 4-12 rep range. Longer sets will see energy systems and pacing strategies impact velocity loss, while in short, high intensity sets the velocity can drop so quickly from one rep to the next that it is challenging to use velocity loss as an effective autoregulation tool (RPE or last rep velocity is more effective for 1-3 reps).
Last rep velocity (LRV)
A novel metric that is gaining interest is to look at last rep velocity (LRV) for a set to measure exertion and proximity to failure as an alternative to velocity loss.
If a lifter knows the velocity of their 1RM, a metric called the minimum velocity threshold (MVT), they can gauge proximity to failure based on how close the last rep of any set is to the MVT and determine how much of a grind that set was.
Any sets that finish at RPE 10 would be RMs and should align with the Minimum velocity threshold value
The benefit of this system is that it is more stable and consistent than velocity loss, but the big drawback is that it requires an accurate MVT, a number that can change over time and can be challenging to accurately measure.
What is my method for working with velocity loss or last rep velocity?
I think the best approach to managing proximity to failure and volume is through a hybrid approach; first learning to gauge RPE with the standard 1-10 system as described by Mike Tuchscherer, then integrating velocity loss stop points for sets in the 4-12 rep range to match your training phase and goals.
At the time of writing I don’t practically apply LRV in my training or coaching, although it is certainly an area of interest for me, especially for powerlifting where the minimum velocity threshold value is more stable and highly relevant to performance.
Range of motion variance
Range of motion (ROM) variance is a way of measuring consistency of technique across a given set.
The smaller the variance value the more consistent technique was across a set was with every rep covering the same distance. This is especially valuable for powerlifters looking to improve their efficiency on the big three lifts, or for novice and intermediate lifters learning how technique adjustments impact their power output and velocities.
Reviewing a set: Takeaways
The ability to interpret data from an individual set is really key to implementing velocity data to improve your training.
Here are my key practical lessons:
- Best rep velocity is my go to metric. It tells me about intent to move, motivation and how much effort is applied on each given weight. This number can be used to monitor readiness between weeks, compete with training partners, or as a way to track progress over time.
- Velocity loss is a powerful complement to RPE for measuring proximity to failure. There is good research highlighting that athletes who take sets to 20-25% velocity loss achieve superior short and long term training outcomes compared to those athletes who train as high as 40% velocity loss. Less work, more gains for strength and power.
- ROM variance can be valuable for keeping technique consistent or to ensure you are moving the bar through the range of motion appropriate to your goals. Setting a ROM goal can be just as useful as a velocity goal especially when it directly impacts sporting performance like in powerlifting.
Continue reading the fundamentals series with part four: profiling a session →
Recap
References and resources
- Hickmott, L, Chilibeck, P, Shaw, K, Butcher, S. 2022. The Effect of Load and Volume Autoregulation on Muscular Strength and Hypertrophy: A Systematic Review and Meta-Analysis. Sports Medicine
- García Ramos, A, Weakley, J, Janićijević, D, Jukic, I. 2020. Number of repetitions performed before and after reaching velocity loss thresholds: first repetition vs. fastest repetition - mean velocity vs. peak velocity. International Journal of Sports Physiology and Performance.