Understanding VLamax

One of the most fascinating metrics offered through INSCYD testing is the ability to measure VLamax, but it’s also one of the most confusing. This is because until recently VLamax hasn’t been a commonly used metric outside of professional sport, and it’s still not a widely offered test in many labs. But understanding it, measuring it, and manipulating it has become a ‘secret weapon’ of sorts for top level coaches and teams.

“Your really know what you need to work on if you know your VLamax“

Dan Lorang, Coach of Bora Hansgrohe Cycling Team and Ironman World Champions Jan Frodeno and Anne Haug

So what is Vlamax?

VLamax is the maximum production rate of lactate in an athlete’s body. Why is this important? Because the lactate produced in your body is proportional to the energy produced by the glycolytic (commonly called anaerobic) system.

So in simple terms, VLamax can be seen as a measure of the power of an athlete’s anaerobic system and their ability to combust carbohydrate to use as energy.

A high VLamax indicates a rider has a well developed explosive kick, and sky-high values are what we’d expect from track sprinters.

However, Vlamax is a double-edged sword. Because we know an athlete who produces more lactate maximally also produces more at lower intensities, a high VLamax doesn’t make for an efficient engine. A higher VLamax is inversely proportional to your threshold power, pushing the threshold down as VLamax goes up. It also decreases the ability to rely on fat as a fuel at sub-max intensities.

As a rough guide, we can expect to see GC contenders around .3 or .35 mmol/l/s. A classics style rider could be in the .4-.6 range, while a sprinter will be above .6, more likely above .7. The very top end could be .8-.9 for a road sprinter, while track sprinters could be higher still.

So how does this change the way we train?

Knowing the VLamax gives us a huge glimpse into our athletes engine that we don’t have only with power output.

For example, let’s take two athletes who are both targeting success in a Gran Fondo style event, long and full of climbing. Assume both athletes are the same size.

Rider A: Vo2max of 70, VLamax of .65, threshold of 350 watts

Rider B: V02max of 62, VLamax of .35, threshold of 350 watts

Rider A and B show identical performances at threshold, but they are nowhere near the same athlete. Rider A has a VLamax that marks him as an explosive rider, someone with a handy sprint although perhaps not quite a pure bunch sprinter. Rider B has a VLamax exactly in the range we’d like to see for the event both riders are training for.

Rider A needs to train in a way that will lower his VLamax. It can be strange at first to imagine lowering a physiological capability in order to improve, but if you think to your experience in cycling you probably already know that the best sprinters never make the best climbers, and vice versa. This is the physiological reason why. For rider A, lowering VLamax will raise his threshold, his fat max, and make him a stronger rider in the event he is training for.

Exact training protocols to lower VLamax can weight for another day, but to give a simple overview, it requires avoiding high-intensity efforts like sprints and anaerobic intervals while spending lots of time doing hard endurance work, tempo efforts, big-gear efforts at sub-threshold intensities, and perhaps some dietary manipulation.

Rider B already has quite a low VLamax, which will be difficult to push much lower. We can’t say for sure without knowing his training history, but we can expect that the best way for him to improve is to raise his V02max.

Doing this will have similar results to lowering the VLamax: raising the threshold and improving fat combustion. Unlike lowering the VLamax it won’t negatively impact our rider’s sprint, which isn’t a concern for this event, but can be in other cases (for example, if you wish to improve a rider’s threshold without negatively impacting their sprint, you must target V02max and not VLamax).

Again, we won’t go too deep into training prescriptions for the day. But raising V02max requires both a high volume of training and high-intensity training above threshold. This athlete would likely want to train with a ‘polarized’ intensity distribution that allowed for lots of time in their endurance zone and a couple of focused, intense workouts well above threshold per week.

Case Study: Tracking the VLamax over a season

Here we have season long data on the VLamax, V02max, and threshold of a World Tour athlete. I’ve included this as it’s a fantastic way to see how targeting the VLamax can be vital to an athlete’s success.

The data above is from an entire season for a top-level World Tour rider. It allows us to see how his values changed over the course of a season, and more importantly, how measuring VLamax was vital to his success.

Pre Season

The rider comes out of the winter with very high values for VLamax. We see right away that with a VLamax of nearly .9, this rider is a sprinter. On the other hand, his values for V02max and VLamax are low.

Early Season

From the sluggish start in November, the riders goes through winter training camps and early-season racing. By the time he tests again in mid-late March, his V02max has gone way up. His VLamax has gone down slightly, but at .8, he’s still retaining his kick. Thanks to that rise in V02max and the lower VLamax, his threshold goes way up as well.

This is a good example of training for a sprinter, maximizing aerobic capacity without damaging the sprint too much. In this case the sprint going down slightly may be planned in order to try to get him to the end of the 1-day Classics, or it may be a symptom from too much racing that begins to show up later.

May

By May, we can see the athlete is getting run down and performance is decreasing. His V02max has gone down, and crucially, his VLamax has dropped to the point that his sprint is compromised.

Notice, crucially, that this drop in V02max combines with the drop in VLamax to leave his threshold in the same sport. Were we only tracking this rider’s threshold, we wouldn’t have an explanation for why he’s seeing a drop in performance. This is a perfect example of the benefits of tracking these metrics.

Tour de France

We see that in May, the athlete begins to incorporate sprint training to target the lost VLamax. He also is pulled mostly away from racing, into training specifically for the Tour. We see he recovers from the fatigue of racing, and both his VLamax and V02max go up. By the Tour he’s at his season’s peak: VLamax back above .8 (nearly to pre-season values), with a high enough V02max that his threshold is at it’s peak as well.

Again, note that his threshold is only very slightly higher than his previous peak for the season. Were we to only watch his threshold, we’d conclude that he was in good shape but nothing dissimilar to previous points in the season. Thanks to tracking the VLamax and V02max, we get the more accurate picture of an athlete at his peak for the season.

Post Tour and late-season

After the Tour, we see the athlete’s values have all declined. This is normal after suffering through the mountains and arriving exhausted to Paris.

After the Tour, the athlete bounces back somewhat, but never to his peak form. This is a good example of an athlete ‘racing out the season,’ fighting fatigue and lowered motivation but still able to perform at a good level.

Want to know more about VLamax, INSCYD, or how testing can benefit you?

Read more about our work with INSCYD here, and get in touch with us to schedule your test.