Are you a cyclist looking to sprint faster than Wout van Aert? Or a triathlete dreaming of racing with Jan Frodeno at the next Ironman World Championships? These may be hard goals, but a good way to start working towards them is to understand a very important metric of human performance: VLamax (also: glycolytic power). During both a sprint and a triathlon, VLamax plays a crucial role.
Never heard of VLamax and this all sounds like blasphemy to you? Read on and you’ll understand.
Before we start, let’s first talk about the definition. VLamax stands for the maximum production rate of lactate in your muscles. Let’s break it down:
Since lactate is produced in the muscle, we say VLamax is the maximum (max) production rate (V̇) of lactate (La) in the muscles.
You probably wonder why you should care about the maximum lactate production. And that’s a good question! To answer that question, let’s look at the 3 energy systems of the human body:
If you want to better understand your sports performance, you need to know how well those energy systems are performing. Especially because they are almost always working together, whether you are sprinting or running a marathon.
Let’s first talk about the VO2max because often the VLamax is best understood by comparing it with its well–known brother: VO2max.
We all measure the aerobic performance, using the VO2max. VO2 max is about the maximum (max) oxygen (O2) volume uptake over time (V̇). This is proportional to the amount of energy (or power) produced aerobically. Therefore, VO2max is a valid marker of the aerobic energy system’s performance.
VLa max is about the maximum lactate production rate. This is proportional to the amount of energy (or power) produced via the glycolysis. Therefore, VLamax is a valid marker of the glycolytic (anaerobic) energy system’s performance.
Do you see the similarities between VO2max as a performance metric for the aerobic energy system, and VLamax as a performance metric for the anaerobic (glycolytic) energy system?
As some call the VO2max, the aerobic capacity or aerobic power – you can also call the VLamax , the glycolytic capacity, or better: glycolytic power.
Watch the summary of this article via this video:
To answer the question “why should you care?”. Because it tells you how well the glycolytic energy system is performing. Unlike the VO2max (which is the higher the better), having a high VLamax can be an advantage or a disadvantage. This depends on the type of sports performance you want to be good at. Let’s learn more about that.
The glycolytic energy system produces energy fast. Therefore:
However, the glycolytic energy system also produces lactate and burns a precious fuel: carbohydrates. Therefore:
This should make clear that all athletes benefit from knowing their glycolytic power, so they can adjust it to their race demands! But how do you know what your VLamax is?
There is no such thing as a VLamax calculator based on certain efforts. To get an accurate value, there are two VLamax test protocols: one that includes a 15 second sprint and one that includes several sub-maximal tests.
INSCYD is the only tool that provides you a scientifically validated VLamax . Even more important: it also allows you to understand how it influences your performance and what your optimal VLamax is.
The INSCYD VLamax test can be performed in a lab environment, but you can also do a VLamax field test and even a remote Zwift test. Athlete’s can do their test via one of our INSCYD coaches. Coaches can start offering these tests by becoming an INSCYD coach:
Once you know your glycolytic power, it’s time to start training. The question about “how to train VLamax” is a bit more difficult than “how to train VO2max”. Why? Because, as mentioned, a highly active anaerobic energy system has both advantages and disadvantages. However, once you know your VLamax and your goal, you know whether to increase or decrease VLamax. Here’s how you can start doing that.
If you want to increase your VLamax, start by making sure you do nothing that decreases it. Next, think about short intervals like sprint training with a lot of recovery in between intervals. Strength training could also be a part of your trainingplan. Get 5 training tips on how to increase glycolytic power via our free whitepaper:
Even though it’s a marker for the performance of an energy system, we often receive questions about “how to lower VLamax“. Reducing VLamax often comes down to making sure glycolytic muscle fibers fatigue, and therefore become more aerobic. Get 5 training tips on how to decrease glycolytic power via our free whitepaper:
As said: some athletes benefit from reducing their glycolytic power while others will benefit from increasing it. That depends on the sport you perform: cycling, running, triathlon, swimming, XC skiing etc. It also depends on the type of athlete that you want to be. A sprint runner needs a different VLamax than a marathon runner.Interested in whether you should increase VLamax or decrease VLamax? National Champion coach Ben Tilus shares how you can find out whether you should increase or decrease VLamax.
Here’s an example of some values:
VLamax values typically range from 0.2 mmol/l/s to 1.0 mmol/l/s.
For comparison: world class marathon runners have a VLamax in the ballpark of 0.3 mmol/l/s. But if you want to run 100m in sub 10sec it needs to be more in the ballpark of 1.0 mmol/l/s.
Scientific literature showed that a female world record marathon runner had a VLamax of 0.31 mmol/l/s.
Cycling Team Jumbo Visma head coach Mathieu Heijboer shares VLamax values of his riders in this webinar.
In the book DER KONA CODE, Sebastian Weber recommends (KONA) triathletes to aim for a VLamax below 0.3 mmol/l/s for women and below 0.4 mmol/l/s for men.
You can use this normative data to understand what you need to work on to get the ideal metabolic profile.
Sprinters need a lot of energy very quickly. For such short, hard efforts, a high-energy production in a small amount of time is needed.
The glycolytic energy system is the solution, because it produces energy much faster than the aerobic energy system.
With VLamax being a measure of performance of the glycolytic/anaerobic energy system, it will come as no surprise that a high VLamax increases glycolytic power and therefore the possible sprint power.
Here’s an example of how the VLamax determines glycolytic power and 12 second sprint power in cycling:
However, always keep in mind that in some sports, the sprint takes place after a long endurance race. For instance in cycling. That’s why some sprinters – like Wout van Aert – still feel the need to decrease their VLamax for better performance. Watch the video to hear what Wout van Aert has to say about it:
Endurance athletes need a good amount of energy for a long time. Examples of endurance events are: long distance triathlons (half and full-distance Ironman), marathons and also bike races. In these kind of events, the key is to go as fast as possible without:
Having a high VLamax does quite the opposite. Even at sub-maximal intensities.
Learn more about the role of VLamaxin endurance performance via our free white paper:
Finally, it doesn’t matter if you’re Wout van Aert or Jan Frodeno. In both cases – but especially in your case – basing your training on VLamax will bring your performances to peaks they’ve never reached before.
Dr. Hellard of the french swimming federation on the importance of VLamax in swimming.
Dan Lorang – coach of Jan Frodeno – on the importance of VLamax in Ironman races.
Is there any INSCYD podcast that does not mention VLamax? Probably not. But if you want to learn everything about it via a podcast, we highly recommend starting with these two.
Want to learn more? Get our FREE whitepaper full of practical tips:
Do you have a question or do you want to learn more about INSCYD? Please reach out via the contact button!
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