Have you heard of the Force Velocity Power (FVP) profile yet? Does the name JB Morin ring a bell? Not really? Don't worry, we'll show you what this Force Velocity Power profile is and what you need to create it.
Table of content
- What is a Force Velocity Power profile?
- What can I do with Force Velocity Power profiles?
- What do I need to make a Force Velocity Power Profile?
- Which input is needed for the Force Velocity Profile?
- How to integrate this into practice?
- How is my input modeled and how do I interpret the Force Velocity Power profile?
What is a Force Velocity Power profile?
When we study athletes, we notice they’re all very different. All athletes have their individual sports performance characteristics and therefore it makes sense to train them in a specific and personalized way. Unfortunately, it often happens that an entire group receives a uniform training program.
This is where the individual Force Velocity Power profile comes in! Developed by Prof. JB Morin, it’s a simple model to describe complex events. Usually, a simpler model helps clarify which of its characteristics are essential to the observed effect, in this case the sports performance.
For isolated ballistic movements, like a squat or a bench press, there’s a quasi-linear relationship between the force and the velocity (Bobbert, 2012). This means the higher the external force output, the lower the movement velocity, and vice versa. This correlation would mean that the stronger an athlete is, the faster they run.
In reality though, this is not the case. An athlete with more maximal force doesn’t necessarily reach more maximal velocity, and being strong at low velocity doesn't always go with being strong at high velocity (Jimenez-Reyes et al., 2018). For example, to be considered a good track cyclist, one has to be strong at the start (at a low velocity) but also maintain this strength during the course of the race (at a very high velocity).
For real life explosive movements, like a sprint, we don’t talk about a Force Velocity relationship, but rather about a Force Velocity profile. When also calculating the athlete’s “power”, which is the product of the force directed in the direction of running and velocity, you obtain their full Force Velocity Power (FVP) profile. This is an individual profile of your athlete where you can see whether their force, velocity and power production capabilities are optimally balanced.
What can I do with Force Velocity Power profiles?
Since it’s a simple model, you can construct an athlete’s Force Velocity Power (FVP) profile with a single sprint test.
Their FVP profile will give you valuable insights into what their strengths and weaknesses are. It can enable you to spot a force or velocity deficit in your athlete and accordingly construct an effective training plan to tackle this deficiency, focusing on force or rather maximum velocity training.
By repeating the Force Velocity profiling, every other week or so, you can keep track of the athlete’s progress and get feedback on their response to the assigned training stimuli and adjust the training plan accordingly.
Keep in mind that the training effects may not be observed straight away. As many coaches probably know from practical experience and as described by Marrier et al. (2017) for rugby players, assessing changes in the athletes’ performance in the week after an intense training block may not show you the correct results. Often a tapering time is needed to get to their peak performance.
For example, when using high resistance sprint training (HRST) to improve the maximal mechanical power output (Pmax) of sprinters, which puts a significant toll on the neuromuscular system, Morin et al. (2020) observed an increase in performance 1 week after the training block (a typical post assessment) but an even greater increase after 3 to 4 weeks! In addition, once again, the adaptation kinetics were very different between individuals.
What do I need to make a Force Velocity Power Profile?
It’s actually pretty simple. You need to do a sprint test between 20 and 40m (the athlete needs to reach maximal velocity) and capture at least 4 split times. Even better would be to capture the speed over time throughout the total run. Below, you can see an example of the needed setup with timing gates and with a Ledsreact Pro
Capturing split times can be done with an app like MySprintApp or at least 5 sets of timing gates, which can be rather expensive. With the Ledsreact Pro, that tracks the athlete throughout their entire movement, or a laser or speed gun, you can capture the speed over time.
Which input is needed for the Force Velocity Profile?
The split times (in the case of timing gates) or the speed and time data (in the case of a speed gun) from the sprint test serve as input to the Excel spreadsheet from JB Morin (Morin, 2019), where some subsequent actions are required. If you are working with a Ledsreact Pro, you just have to synchronize your data and our cloud processing uses the speed data over time to do the rest.
Next to the data from the sprint, you’ll also need to fill in the height and mass of your athlete, the outside air temperature and air pressure.
You can look up the air pressure of your location with a more advanced weather app or via this site or example. Standard values for these last parameters are 20 degrees Celsius and 1000 mmHg. For US people, remember to convert the units from Fahrenheit to Celcius and from inHg to mmHg!
The outside air temperature and the air pressure, together with the height and mass of the athlete are used to calculate the air friction when the athlete moves through the mass of air. The mass also comes into play when calculating the horizontal force.
The most important thing to remember here is that the quality of your input determines the quality of your output!
To get correct results, the time measurement should start from the first propulsive action of the athlete. This can be tricky with GPS for example, because on the basis of GPS data it’s hard to determine when the athlete really initiated their sprint.
It’s also important to really start at 0 m and from a stand still. In many test settings the timing gates are placed 30 or 50 cm in front of the start line and this introduces a big offset in the data and leads to overestimations of your athletes.
The Ledsreact Pro tracks the movement of the athlete, thus making it possible to exclude the reaction time from the total time. This type of tracking also makes sure the time measurement can start at exactly 0m and will end at the correct distance, which it measures out by itself, thus taking away some of the human error.
How to integrate this into practice?
Force Velocity Power profiling can become a very strong tool in your arsenal to elevate your team’s performance. The research done throughout many different universities and research groups has tremendous value for both amateur and professional teams. Even though it might take some time to initially set this up, it will be totally worth it.
Some people might say that FVP profiling is hard to use and that it requires time and effort to run the calculations. While that is true, it’s also made easier through the excel file that was published by JB Morin. If you have a Ledsreact Pro device, you will find the functionality in the graphs on the web platform when you perform a sprint test of minimum 20 meters or yards (Long Sprint or Sprint Test). This feature in our software basically means that you have no extra work at all, apart from analyzing the results and building individualized plans.
To implement FVP profiling into your test protocols, there are but a few steps to follow.
- Conduct sprint tests of ideally 30 meters with your team and collect intermediate times as well.
- In the case you don’t have a Ledsreact Pro, use the intermediate times as input in the JB Morin spreadsheet. If you have a Ledsreact Pro, go to the web platform where the results of the test are shown.
- Analyze the results and group your players according to their FVP profile.
- Design an individualized training plan.
- Repeat this test every two weeks to keep track of your players' progress and update their training plan accordingly.
How is my input modeled and how do I interpret the Force Velocity Power profile?
Check out our follow up blog post to understand how the Force Velocity Power profile is built and what you can do with it.
Bobbert, M. F. (2012). Why is the force-velocity relationship in leg press tasks quasi-linear rather than hyperbolic? Journal of Applied Physiology, 112(12), 1975-83. 10.1152/japplphysiol.00787.2011
Jimenez-Reyes, P., Pierre, S., Garcia Ramos, A., Cuadrado, V., Brughelli, M., & Morin, J.-B. (2018). Relationship between vertical and horizontal force-velocity-power profiles in various sports and levels of practice. PeerJ, 6. 10.7717/peerj.5937
Marrier, B., Robineau, J., Piscione, J., Lacome, M., Peeters, A., Hausswirth, C., Morin, J.-B., & Le Meur, Y. (2017). Supercompensation kinetics of physical qualities during a taper in team-sport athletes. International Journal of Sports Physiology and Performance, 12(9), 1163-69. 10.1123/ijspp.2016-0607
Morin, J.-B., Capelo-Ramirez, F., Rodriguez-Pérez, M. A., Cross, M. R., & Jimenez-Reyes, P. (2020). Individual adaptation kinetics following heavy resisted sprint training. Journal of Strength and Conditioning Research. 10.1519/JSC.0000000000003546
Morin, J.-B., Samozino, P., Murata, M., Cross, M. R., & Nagahara, R. (2019). A simple method for computing sprint acceleration kinetics from running velocity data: replication study with improved design. Journal of Biomechanics, 94, 82-87. 10.31236/osf.io/vgqzs