Cheat School: 6. Optimizing the First 20 Min

In the previous lesson we learned how to manage the trailing 20 min W/kg average so that the highest such trailing average in a race does not reach the performance ceiling in your cruising cat.

We made the distinction between 20 min blocks on the one hand, which any race can be divided into, and on the other hand 20 min periods, or trailing 20 min averages, which is what ZP measures and which can intersect two 20 min blocks.

We also said that in most races the highest 20 min period in your race, which ZP will judge you by, is likely going to coincide with the first 20 min block since it includes the start, where everyone typically pushes hard for early positioning, thus driving up the average.

But is it optimal to push hard the first 20 min? What does in-game physics have to say? Let’s find out!

Zwift physics is modeled on real life cycling physics. I wouldn’t say this has been tested thouroughly yet, but all the little studies so far, and some of them you can find on Zwift Insider if you dig around, indicate that, although with some convenient simplifications, Zwift closely follows the generally accepted physics model of cycling, parts of which was published in a report by Martin et al (1998) but which is fundamentally plain old Newtonian physics. And this matters because it helps us make a crucial (cruisial) prediction regarding the first 20 min of the standard race.

I’ll throw some physics in your face:

These hieroglyphics are not nearly as difficult as they may seem at first, so bear with me for a minute. The above formula can be used to calculate the power in Watts needed to pedal your virtual Zwift bike forward on a flat surface, a simplified case but the Tick Tock course does spring to mind. Let’s pick the formula apart.

P is power in Watts. Fv or F * v is force, measured in Newton (like on your expensive Park Tools torque wrench), times your speed. They are the same. It’s how you can define Watt.

Then comes an expression in two parts. First is the Cr * m * g * v. It’s the contribution of rolling resistance. Friction between wheels and tarmac and friction within the drive chain means you don’t get fully rewarded with speed when you pedal. Some is lost due to rolling resistance and you need to counter it. Little is known about how rolling resistance is modeled in Zwift and it really doesn’t matter for our purposes. Likely it’s just a fixed number regardless of rider and chosen bike. For simplicity, let’s assume it is zero, no rolling resistance to worry about.

Then comes the second part of the formula on the right hand side, and this is where it gets interesting. The second part says something about air resistance, or drag. There is no wind in Zwift but it seems drag is accurately modeled.

The second part of the expression is ½ * Cd * rho * A * v^3. (It’s not a ‘p’, it’s the Greek letter rho, but that’s unimportant.) What does it all mean?

Cd is the drag coefficient. Every 3D geometrical shape, or its front side rather, has its unique Cd, we could say. A low number is preferable because that means we will need to push a lower P, Watt, to keep the bike moving. A ball-shaped object has a lower Cd than a cubic object, e.g. a cardboard box. A pointy bullet or a rocket has an even lower Cd than a ball. And an aero bike frame has a lower Cd than a MTB. What about the rider? Even though it is a simplification, Zwift most likely sets a fixed number for any rider regardless of their real-life bodily shape.

The funny looking ‘p’, rho, is air density. The thickness of the air. We don’t normally think about air and the resistance it actually gives unless we take a walk on a windy day. Or when we get on the bike outdoor and try to be fast. In complete vacuum, like in outer space, rho would be zero, because there is no air at all there. And when you multiply something by zero, it becomes zero. So if rolling resistance is zero, which we assumed for simplicity, and if there is no air, then no power is needed to keep a certain speed on your space bike. You just need to worry about the initial acceleration up to the speed you want to keep, but that’s a different formula. This is the reason why it is possible to go back to Earth from the Moon without a crap ton of fuel or why a satellite can go around the Earth at very high speeds without using any engines – in vacuum you just keep going. But down here on Earth we have to keep applying Watts to keep the speed. And the closer to sea level we are, the higher the air resistance because the air density is slightly higher due to gravity, whereas the density is slightly lower at high altitude. So what about Zwift? The Zwift physics model is probably simplified, meaning air density is just a fixed number regardless of whether you ride the Ocean tunnel or sprint to the finish on Ven Top.

Next comes the constant A. That is you and your bike’s frontal area measured in square meters. A big frontal area gives high air resistance. This is how a sailing boat can go forward without an engine. A huge frontal (or aft) area in the form of the sails, the bigger the better, sort of. But for a bike rider you want it as small as possible. Aero frame. Aggressive riding posture. Etc. Like with Cd, the drag coefficient, a smaller frontal area means you can push lower Watts to keep a certain speed. Frontal area has been shown to vary among bikes and riders in Zwift. A short rider is more aerodynamic because he has a smaller frontal area. Possibly, although not quite confirmed, a tall light rider has a smaller frontal area than a tall heavy rider in Zwift. Outdoors this is so. But regardless, like with the drag coefficient and air density, this is a constant that you cannot change (unless you lower your height in the Zwift settings). These factors are what they are for you in any race.

So what the hell does all this have to do with the first 20 min when cruising a race? Well, there is one more factor to consider, the cruisial one. Next and finally comes v^3, velocity (or speed in meters per second) raised to the third. A cubic speed. And this has huge implications for Zwift racing in general and for the first 20 min when cruising.

Let’s visualize with the help of some fictitious and simplified (an thus unrealistic but illustrative) examples. Let’s assume rolling resistance is zero. Let’s assume Cd, rho and A are all 1. So then the Watt needed to keep a certain speed, v, is:

P = 0 + ½ * 1 * 1 * 1 * v^3

which is the same as

P = ½ * v^3

So under these artificial circumstances, the Watts needed to keep 25 kph would be:

P = ½ * …

Wait a minute. v is measured in m/s in Newtonian physics, not kph. We need to convert 25 kph to m/s. 25 kph = 6.9 m/s.

P = ½ * 6.9^3 = 164W

These are unrealistically high Watts. That’s just because we set the other factors to 1. They are constant and don’t change and they are lower than 1 in reality. But it keeps the example simple, so let’s stick with those numbers.

What about keeping 30 kph instead? 30 kph = 8.3 m/s.

P = ½ * 8.3^3 = 286W

But that’s no way to start a race. If we were to race a TT without drafting in the lower categories we might want to go at 35 kph. 35 kph = 9.7 m/s.

P = ½ * 9.7^3 = 456W

In a normal race we would be drafting in a group as cruisers. So we would probably be looking at 40 kph on the flat mid-race rather than 35 kph. 40 kph = 11.1 m/s.

P = ½ * 11.1^3 = 683W

But we were supposed to talk about the first 20 min. At the start everybody will be pushing hard. We would want to go at 45 kph at least to keep up with the others. 45 kph = 12.5 m/s.

P = ½ * 12.5^3 = 977W

Nah, let’s stomp it at start and sail with the sandbaggers for a bit and then compensate the high initial Watts by going under cat limit for the latter part of the first 20 min. Let’s do 50 kph at start! 50 kph = 13.9 m/s.

P = ½ * 13.9^3 = 1342W

Hmm… there is something going on with the Watts needed. And it has to do with raising speed to the third in the formula. Let’s visualize it in a graph.

We can see that the line is not straight. The relationship between speed and the Watts needed to keep it is not linear. It’s cubic. This means that for every additional kph we want to add to your speed, the Watts needed to drive it grows exponentially. It is not hard to keep 20 kph even without drafting. To increase speed by 10 kph to a total of 30 kph is harder but still not hard. But to increase with yet another 10 kph up to 40 kph is notably harder even though the speed increase (10 kph) is the same in both cases. And going 50 kph without drafting starts to get really hard. For some people it will mean actually sprinting, something you can’t keep up for long.

So what about the first 20 min then? Let’s simplify again. Assume that the cat limit translates into the W/kg needed to go 40 kph. And assume that you have the choice between going a steady 40 kph throughout the first 20 min and going 50 kph for the first 10 min and then 30 kph for the last 10 minutes to compensate for the hard start. (50 + 30 ) / 2 = 40, so the average speed would be the same in both cases.

In the first case, a straight 40 kph for 20 min, would mean 683W with our simplified and exaggerated numbers. And let’s say 690W is the cat limit. You have nearly optimized the first 20 min then, all else equal.

But what about the hard-start option then? For the first 10 min you go at 50 kph, meaning 1342W, and then 30 kph meaning 286W for another 10 min.

(1342 + 286) / 2 = 814

So by going hard rather than keeping an even pace in the first 20 min, your Watts needed jump from 683W to a whopping 814W! And if the cat limit for you with your weight was 690W, then you would go over limit by a mile and get a WKG on ZP.

In a real Zwift race the drag coefficient and the other constants will be lower, so the actual Watts needed will be lower of course. But the cubic relationship between Watts and speed remains the same. It is much more efficient to keep an even speed just below limit in the first 20 min block of a race, or actually at any point in a flat race.


Can you? There could also be tactical considerations to take into account, things that might force you to go hard at start. Let’s assume, again simplified, that at start you have the choice between two groups. The front group is full of sandbaggers and will keep a speed above your limit, so you can’t stay with it for long. But later in the first 20 min the group will shatter into two and you could go with the slower subgroup and keep within limits. Or you could go with the second group which ends up traveling at a decent margin below cat limit. Although going with group two will safeguard your average, you will be going too slow later in the race and will probably miss the podium. Trying to bridge to the slower part of the front group from group two would mean pushing very hard Watts solo without draft later and might not be possible.

So there are reasons, fuzzy uncertain factors to consider, when choosing speed in the first 20 min block. But you should be aware of the… let’s give it a cool name, the Cubism of Speed, when you cruise. The best thing to do is rarely to go with the worst bunch of the sandbaggers at the start, even if you intend on dropping later in the first 20 min block. It is a better choice to look for a somewhat slower group already from the start, a group that you will have to drop into later anyway as you drop from the sandbaggers. And when you have dropped into that somewhat slower group, your average will be higher than theirs because of your early sins at the start. Very important point! So it would have been better to go with the slower group already from the start. Going too hard at start is a complete waste of useful W/kg wiggle room as a cruiser. It is what is going to prevent you from having to drop to save your average if there is an early climb, or what is going to prevent you from bridging to a somewhat faster group if it turns out your group slows down too much.

But what about drafting? Drafting means you get less air resistance, right? So how does that affect the whole argument? If you can secure good drafting in the first 20 min, wouldn’t it change things? No. Well, a little bit. But in the two group example we assumed draft in both groups. And the way draft is calculated in Zwift, it seems it gives at best something like a 30% reduction in drag. But even so the cubic relationship between Watts and speed remains, although with this reduction. If the choice is between going with a fast group in draft and going solo behind them at start, then provided the fast group doesn’t send you over limit, in which case you would have to drop anyway, then going with the group is the better option because of the 30% reduction. But in most cases when cruising you should avoid taking wind like the plague anyway, regardless of which group you choose to go with. Cruisers suck wheels and only take wind when attacking.

So how do you choose the optimally paced group at start then? Well, that is more an art form than science, at least then and there from the saddle with numbers and riders flashing on the screen all over. It will take a lot of practice. Practice with caution. Err on the side of prudence, push it slightly more in the next race instead and you will have a long and fruitful career as a cruiser. Good luck!


Race Report: CeramicSpeed Series Qualifier Race – How to Cruise Out and Back Again

This was one race I just had to cruise! Sponsored event featuring a high-profile brand. Is there ever a better opportunity to display the filth Zwift swept under the carpet? Now, nobody is interested in anything but cat A here. They are the ones to be crowned ambassadors, i.e. a few of them will get to be a virtual ad sign for a bit. Almost like going pro, no? Well…

For best effect, although from a low category, you would of course want to win an event like this as a cruiser, and then brag openly about how you cheated yourself to a win… without actually breaking any rules. If it wasn’t for the usual cat A focus, I would be furious as a sponsor with a brand name to protect if I was fully aware of what a piece of unfair crap Zwift racing really is. And as an undercover cruiser I would just love to help create a little awareness.

The only problem was this was going to be a very difficult race, for a number of reasons.

First, the start list was huge. Three minutes before start I counted 98 ZP registered participants and a few more probably dropped in while I warmed up. We can safely assume there were many unregistered as well even though the rules said you needed to be registered in order for your result to be taken into account, although in the end only 86 finished in cat D. It was a long and tough race that would still attract a lot of people who don’t race regularly and who then got more than their fill during the race and bailed out. Anyway, it is more difficult to cruise a big field since the probability that there is someone in the race who can beat you increases with every additional participant.

Second, how can I be so sure there were lots of unregistered without actually looking? (I never bothered.) Well, it’s a fair assumption that people just wanted in, not caring too much about the rules, since there were plenty of sandbaggers too. I counted 33 cat C’s or worse 3 min before the race. They would all get UPG’s of course, but that didn’t stop them from joining. There were probably quite a few unregistered sandbaggers as well. And cruising a race with a lot of sandbaggers in it is difficult for two reasons. They may confuse you and have you believe they are threats to your placing, and if you don’t watch it you might be tempted to follow which could bust your 20 min average. Also, perhaps even worse since you can’t control the damage yourself, sandbaggers set up the heavies for a win. As a light cruiser I can’t follow a sandbagger for long or I will go over limit. But a heavy might be able to suck the slower sandbaggers’ wheels and still stay within limit e.g. by getting early separation in the first minutes that may be hard to bridge, if you are even aware of their presence somewhere in the far distance in front of you.

Third, an additional problem with huge start lists is that they are near impossible to keep track of during the race. Who is in your group at the moment? Are they on the ZP registered list? Are they strong, will they last? Are they legit, sandbagging or cruising? With so many participants you would need your own personal directeur sportif to shout in your ear what to do and how to respond to what is going on around you. Do the dishes and call in the favor from next-of-kin is my advice. It would actually be really useful when cruising. (I do the dishes and more but I still don’t get my directeur sportif – life isn’t fair!)

Fourth, I noticed many threats in the start list. There was an unusually large number of “nearly C”, loads of heavies and quite possibly cruisers too (I didn’t have time to go through the race histories of all the stronger participants of course).

Too many factors to control. I would have to focus on my average and just play the race by ear. The result? It was OK, I think. I got a 5th on ZP and missed the podium (the bronze to be specific) in a sprint, and if you have read earlier posts you may recall that I am not a strong sprinter.

Actually, it was a mistake to allow the short sprint to happen at all. I was planning on doing the usual thing and go on a push or long distance sprint about a km from finish, but being low cat C trash and after quite a few races recently I must admit I was a bit tired and decided to gamble instead. In hindsight it might not have mattered to the result, looking at the race histories of the small group I was in, but at least there would have been no real downside to trying the long sprint as the worst that could have happened was 6th. Note to self: Don’t let it go to a sprint ever again if you can avoid it…

So what about the rest of top 5? The race was won by a superheavy who finished minutes ahead of us. Since all my 20 min blocks (3 ½) were near limit I know for certain that it would have been absolutely impossible to stay with a guy like that without getting a WKG, not that I ever even knew of his presence ahead in the race. He was pushing almost 300W!

Silver was a heavy who worked hard and who I think pushed solo for the last stretch, which kills speed quite a bit. If a long sprint would have been successful (I doubt it) I just might have connected with him, but then he would have destroyed me in the sprint as I would have been toast and wouldn’t be able to match his Watts even if rested.

As for the little group I was in, which included 3rd, we were all cruisers except for 6th who worked hard and had a legit history. He had a clear weight advantage on me but most of the others beat him on the scales, so all in all he was double disadvantaged. If I could pick a deserving winner in this race, it would be him for sure.

How to cruise Out and Back Again then? I think the easiest cruises would come in cat C. The reason is that the Volcano KOM would start just outside the second 20 min block for them. So they would have somewhat better opportunities to go rather hard in the climb in a sort of late post-20 min push, and then recover the average in the descent. But that is only the forward 20 min average covered, and there are good chances of getting your 20 min average starting at the foot of the climb recovered with the help of the descent as parts of it can be supertucked. If the tempo was only slightly below limit in the approach to the Volcano KOM, however, then there would obviously be the risk of raising the trailing 20 min average above limit.

Note: In this race I actually had to drop in the early climb to get my average down before 00:40:00. Then I went on a hard P20P push. It was probably what caused a best 20 min average on ZP slightly above limit and gave me an upgrade post-race (the result still stands though). Doing so helped me reconnect with the riders I later finished with though, so the result would probably have been worse if I hadn’t pushed. But be wary of your trailing average in that climb. It could easily rob you of your cheater’s license.

The Zwift KOM reversed, which is also included in this course, happens at a relatively safe distance in time from the Volcano KOM. So just be mindful of your average as usual there, no special treatment needed. Apart from those two climbs the rest of this longish race is pancake flat favoring the heavier rider. And for the heavy rider able to ride at limit for the duration of the race (essentially cruising, since this is a 60+ min race in cats C and D) not even the climbs will set him back.

As a final note, am I sorry about the upgrade? Not at all! I was about to write something about it a few days ago that it was probably about to happen soon and that I wouldn’t go out of my way to avoid it. Racing is my preferred WO and cruising is really bad for your fitness if you, like me, have the physique where high intensity gives better results than quantity, the long and slow. As if I would have the time anyway… So back to bottom cat C again where I belong right now. I will likely keep posting even so with course advice for the cruiser, more dissections of the Zwift racing system, etc. Oh, and a new data analysis festival – new and improved, smoking hot and shocking – that I have planned for when I get the time. But first that new lesson in Cheat School that I promised the other day.

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Race Report: 3R Racing – How you are forced to cruise Petit Boucle even when you are not a cruiser

Sunday is the day when a lot of Zwifters go on longer endurance freerides. Some choose to join longer races in a lower category instead. Far from all of these sandbaggers are out to snatch a podium. They may grow restless after a while, however, since virtual endurance rides, although essential in many training plans, are terribly boring and since racing other people is much more fun.

Yesterday’s race was one such Sunday race on the longer side. This was the shortened Petit Boucle of 45 km, but with a climb in the latter half it will still take cat A just over an hour to complete. I doubt you could go any faster than 1:15 in cat D.

It wasn’t a well-attended race but with the increased subscriber count there were still a decent lot at the start line. Only a minority were registered with ZP and a majority of participants, registered or not, were sandbagging.

With a race of this length lasting over an hour a cruiser does not worry about legits at all. It is just other cruisers, particularly the heavy ones, one has to keep an eye on. This was rather easy this time since there was just a handful of names that had to be watched. And with only four legitimate finishes in the end according to ZP (me being one of them) this was an easy gold (14th out of 35 on ZHQ).

So let’s forget this race and talk about Petit Boucle instead. It is not a difficult course to cruise at all. At a quick glance the course profile looks potentially complicated but it really isn’t, at least not in cat D and probably not in cat C either.

Most of the course is flattish with just some low-gradient rollers strewn out here and there. There are three climbs, at least if you look at those websites that detail the Zwift courses, but I beg to differ. I would call it 1 ½ climb.

First, there is the Aqueduct forward climb, which is very short and goes into the second 20 min block, and so it is not a problem. Second, there is the Petit KOM, which is a mid-range climb, although I would rate it a little less taxing than Box Hill. Then towards the end there is the Aqueduct climb again in reverse, which isn’t really a climb at all since you gained most of the elevation already earlier in a 2-3% inclination stretch not associated with the actual climb itself.

The Petit KOM could have been tricky. However, it so happens that it fits nicely into the third 20 min block in cat D and probably in cat C too. Since it is a long race, chances are that the last half of the second 20 min block had your group slow down a bit and go under limit. So even if you are forced to avoid getting dropped or elect to push yourself in the Petit KOM, you should be able to accomodate those extra Watts in your 20 min trailing average without too much difficulty. In fact, if the start was hard it might even be difficult to go over limit here with everyone being a bit toasty – it all depends on how low you cruise.

Bear in mind, though, that the descent is not quite as nice and steep as the course profile on some site would have you believe. It can actually be surprisingly difficult to get into supertuck in the descent. You will get the chance to get some CO2 out of your lungs if you went hard in the climb, yes, but the net effect on your average may be smaller than you hoped for. So don’t overdo the climb unless you have a solid plan for keeping your average within bounds.

In an everyday race the rider texture in the last 15 km after the Petit KOM is likely to be rather fragmented. You therefore don’t have to worry too much about finding draft. It is not out of the question to treat those last km’s as a threshold interval (even though it is not it may still feel that way at that stage) and convince yourself you are Jensie. You might not be as stuffed with chemicals but you are a kroozer, ja? So it evens out.

There is one tricky thing about Petit Boucle, though, which I would like to address. It is not something particular to the course really but rather something pertaining to its length. In a longer race like this, on a course that isn’t pancake flat, there may be a whole lot of fighting for position at start. Assume you are a completely legit top cat in C, not an “Almost B” but a solid C, only on top. You don’t podium much, if at all, because the cruisers and heavies do that for you. But you can produce a 20 min average not too far from cat limit. Now, if the race is even half as full of sandbaggers as this race was, particularly if the number of potential legits is a little bigger than in this race, then you might get dragged into these position wars in the first 10 min. And even if the group you are in halfways through the first 20 min block slows down a bit, it might still not be enough for your average to recover in time for the second block. You could risk a WKG, which would be both ironic and unfair since you are forced to spend the latter 20 min blocks well below cat limit due to fatigue. Thus, even a legit rider needs to learn how to cruise, or you risk getting upgraded and then race mostly below your new cat’s W/kg span. It’s a shitty cat system, I know. And Petit Boucle could be one of those courses where you get more than a whiff of the poo. So stay safe in sunny virtual France, whatever staying safe means to you.

We will take a closer look at the first 20 min in an upcoming new lesson in Cheat School. Stay tuned.

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Race Report: ABSA Cape Epic Stage 3 PB Abus – How to Cruise Jungle Circuit (Reverse)

I got the bronze here and I am satisfied. It wouldn’t have been possible with a higher placing. I will explain why later on but essentially it was because of my low weight.

This was a tricky race on a very simple course. The tricky part was the lineup. Since this is a big ZHQ event it attracts a lot of attendees even on a Friday night. I noticed 2 min before race start that the start list consisted of what looked like 50% sandbaggers and higher-cat recovery riders, and that was only on ZP. The bronze on ZP translated into 27th out of 89 in cat on ZHQ!

I also noticed in the ZP start list that there was a 7 year old Canadian child with a 3.2 W/kg 90-day average weighing in at 30 kg. If he finished, then there was no way I or anyone else could beat him since he falls under the low Watt–low weight ZP rules and can legitimately win even though he breaks through the performance ceiling in cat and rockets out into space.

The start was hardish but the front group soon slowed down and the second group bridged to us. Everything was nice and easy with a draft speed giving me a decent margin below cat limit that would surely let my initially high average tick down well before the 20 min mark. But once we hit the caves this kid does the smart thing. Or rather, you could almost hear coach daddy yell in the background “Go Charlie!” He suddenly started pushing 3.2 W/kg and went flying. Since the now enlarged front group consisted of quite a few sandbaggers the group was baited into following. A brilliant move! And well-timed. If there were any ZP signups among those who got baited, then they would be screwed. They would never get their averages down in time. I quickly decided to drop of course.

I expected more riders would be sensible enough to drop but apparently nobody checked the ZP signup list (a good sign, because all cruisers do). Or maybe they were sandbaggers all of them. I dropped into a sizeable group right behind us but even they seemed to be all sandbaggers and intent on catching up with the front group. So I dropped down further into some stragglers. Who were also sandbaggers and intent on catching up with the second group. And so on. It took a while until I found draft at a reasonable pace.

The group I landed in let me lower my average in time and with a nice little margin on top that I could use to catch up with riders up front in a post-20 min push once the first 20 min block was finished. I connected with a couple of riders in the push. After a while some others connected and we turned into a group of maybe six or so riders.

However, on the second lap I still had a Watt debt from the P20P to pay for and the pace was a little too high for my liking. So when the group started to chase down stragglers with 5 min left of the second 20 min block and with my average still 4% higher than my 20 min Watt limit, I realized I had to drop again. The only problem was this group contained the rest of the would-be podium, both of them significantly heavier than me. 1st would go over limit quite a bit in a way that I couldn’t possibly have matched without getting an upgrade. 2nd had 24 kg on me and I wouldn’t be able to compete with such a heavy-weight advantage either. Both seem legit though and if we disregard the Light Rider’s Curse for a second their placings were well deserved.

Some semi-dispersed riders right behind seemed to go a little slower and I dropped back to them. After a while we coagulated into a new group of 6-7 riders. I must have pissed off, among others, future 4th on ZP (who I noticed was a heavy as we went on) since I refused to take wind. I’m quite good at that. I’m glued to their wheels and there is no point in trying to shake me off. It won’t work unless they are sandbagging. And I absolutely had to suck wheel to lower my average in time for the start of the third 20 min block.

I let my average run past 20 min as we approached the finish through the caves. We had slowed down further and I built up a 2% Watt margin I would be able to use at the finish. Not much but it would cover a short push at least and I had saved an Aero powerup too.

The start list on ZP was hard to read with half of the participants, interspersed, being sandbaggers, but I was pretty sure my group only contained one ZP legit rider, the heavy guy I mentioned. If he decided to sprint at the finish just for the hell of it, then he would likely outsprint me and I wouldn’t even be able to try without risking an upgrade. This is a common problem for the cruiser. You will often not be able to sprint at the finish without screwing up your 90-day average, since you are often already on or very close to the limit. And even if, as in this case, you have a small Watt margin up to your Watt limit as you approach the finish, a 20 min average will rise horribly fast if you start doing sprint Watts. It is very easy to bust out in a sprint, so beware.

I pushed semi-hard some 400m out and popped the Aero. Some other guy I was half sure wasn’t on the ZP list went after me and I let him pass while trying to keep 4th behind me with an average that very quickly rose slightly higher than I wanted it to. Luckily, it seems the Wahoo app overreports compared to ZP (or maybe ZP underreports) so there seems to be a little safety margin built into my cheating setup. And thus I could both finish third and stay in cat.

But what about the kid? Well, 7 years is awfully young. If they have the stamina to last 2 laps around Jungle Circuit at all, then very few would have the attention span or motivation to sit through the whole race. In fact, as a parent I’d be slightly worried over a kid who did. On the second lap I saw him standing still by the roadside. Maybe his favorite cartoon had just started. ‘A’ for effort nevertheless.

So how do you cruise Jungle Circuit. Well, there really isn’t much to say. It is a very flat course. You just maintain your average and monitor the tactical situation basically. It won’t be the course itself that destroys your cheating dreams but, if anything, other riders.

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Race Report: 3R Innsbruckring Flat Race 2 Laps – How to Cruise Innsbruckring

This was a ridiculously easy race. The reason was that there were no cruisers around this time, only the usual sandbaggers, but even they were quite few, at least the ones that didn’t actually treat the race as just a moderate workout or recovery ride. Also the race had a distinct lack of strong heavies, which is a bit unusual. Maybe it was the late hour, a little too late for the Euros and a little too early for the Americas.

You can see the lack of competition in the results. You shouldn’t be able to win the golden turd after two measly laps around the Ring with a whopping 2 min time separation between you and the runner-up. It ain’t right. Obviously the remainder of the classification is legit. Note that almost four times as many riders were discarded by ZP, most of which were not registered on ZP at all. But at the same time it is interesting, because the results above tell you something about the power of cruising. It is quite clear. Remove weight advantage and competition between cruisers and this is what you get. Total domination over people trying to ride fair, even on such a short course. It ain’t right. But this is happening all the time in cats B, C and D on a daily basis.

As a sidenote, it’s an encouraging observation that so few among the corona mass invasion of new subscribers actually bother to sign up with ZwiftPower. ZP has its place, for all its shortcomings, and that is for managing leagues and series. But it ends there. And without that false shine of fairness that ZP painted over Zwift, it becomes blatantly obvious how flawed racing in Zwift is. The standard newbie discussion thread about racing these days is no longer the “Why do so many people sign up in the wrong cat?”, but rather the “How come people do 3.5 W/kg in a cat D race when D is specified as 2.5 W/kg max?” I.e. the newbies look straight at the ZHQ classification for the “true results” these days and couldn’t care less about the contrived ZP. And even the yea sayers, you know, the guys who go “You must look at ZP! ZP is da troooth!” seem far fewer in between these days. Or they simply drown in the noise of the newcomers, I don’t know.

Anyway, during prime time hours and with 3-4 laps around Innsbruckring rather than just 2, then you’d see much stiffer competition. I actually ended 4th here according to ZHQ after deliberately giving up the sprint for 3rd to an unregistered sandbagger I spent most of the race with, this in order to keep my average low, because there are a couple of tricky things about cruising the Innsbruckring. And I wanted to talk about that.

How do you cruise the Innsbruckring? It’s a great course and thus very popular. But it isn’t as easy to cruise as e.g. Sand and Sequoias or the other top choice race courses. And the reasons for that are two things. First, it’s a short lap of just 8.8 km. Second, the Legsnapper.

The Legsnapper is the 450m 7% climb towards the end of the lap just after you cross the bridge back to the north bank, just before the 5 km mark. People like to push it there. It presents an opportunity to drop people on an otherwise very flat course. However, pushing up the Legsnapper spells trouble to the cruiser.

Due to the short lap, if you are cruising in cat B or C, then you will hit the Legsnapper twice in the first 20 min block. Let’s say you cruise cat C. The start will be hard as usual, “fighting for position”, which translates into “finding the optimal group to suck wheel in just around cat W/kg limit”. A couple of kilometers after the start your hopefully optimal group will slow down. If the group is indeed optimal it will slow down below cat limit so that you can start lowering your inflated W/kg average (which is nowhere near 20 min yet by the way).

Then right before the 5 km mark comes the Legsnapper. Sandbaggers and contenders will start pushing and you can’t allow yourself to be dropped solo, not unless you have a juicier group right behind you to drop into the open arms of. And what if your current group will slow down considerably after the climb? Then you should be in it. No, you don’t dare to drop. So you follow. Obviously you won’t be trying to drop anyone yourself on the first lap. In 9 cases out of 10 it will be a bad idea. Instead you just follow and make sure you can draft the descent to start mitigating the sudden rise in your previously dropping average. So let’s assume you do and that the group does indeed slow down so that your average starts ticking down nicely again.

But then after another 8 km comes the Legsnapper again! And this time you may not be able to follow your group in the climb, because you are still inside the first 20 min block. In cat C and given that your group slowed down considerably after the first Legsnapper, then maybe. But it’s iffy. If you cruise cat B and given competition from other cruisers, following your group up the second Legsnapper can be a complete no-go depending on the situation. You may find yourself crawling up instead, in panic over your average.

Cruising cat D is easier. Deceptively easier. You will hit the 20 min mark right before the second Legsnapper. So you’re cool, right? No, not necessarily. This is the kind of course where you risk an overlapping peak 20 min period somewhere between the first two 20 min blocks. So unless you can track a trailing 20 min average in realtime, then you have to be careful.

The reason why you need to be careful is that potential overlap. The standard scenario in a race is that the first 20 min block is where you will push your highest Watts due to the hard start. So the 20 min average shown on ZP will be based on the 20 min period coinciding with the first 20 min (block) of the race. But you already have another power peak in the first 20 min block, the Legsnapper on the first lap, and people like to push the Legsnapper so hard that your Watts may become higher even than your Watts at the start, especially on the second lap, since you were smart enough not to follow obvious sandbaggers at the start but tried to find the frontmost group containing cruisers and legits. See the problem?

The problem is that even though the start was lower Watts than the second Legsnapper, there was still higher Watts than your group is now doing on the flat, so the start Watts are still a liability backwards in time, in your actual trailing 20 min average. So if you can’t track your trailing average in realtime but instead rely on the method I proposed in lesson 5 of Cheat School, i.e. restarting the average after the first 20 min block, then you risk going over limits if your group pushes really hard up the second Legsnapper.

This is a big problem for cat B and C cruisers. For the cat D cruisers I would suggest you don’t reset the average as you hit 00:20:00. What you can do instead as a rough method – and this you need to keep in mind already at the start of the race – is to make a mental note of how many minutes you went over limit after the start. Also try get a rough estimate of the kind of W/kg you did up the first Legsnapper. If you went over limit for 2 minutes at the start and if you are not really going harder up the second Legsnapper than up the first, then let your average run for about 2 more minutes before you reset. And keep your average in check. Yes, that could imply dropping.

If, on the other hand, you do indeed go harder up the second Legsnapper, then it gets even trickier. You may have to let the your first average run a little longer, but you could also be past the second Legsnapper after 22 min, which would reduce the risk of going over limit. Make sure you get good draft and hopefully easy pedaling in the descents, because you really need to get your average down a bit immediately.

Finally, there is one more hazard on the Innsbruckring. Because of potentially dangerous overlaps of 20 min periods between 20 min blocks, the finish can also screw up your peak average in the race and send you out of the podium or even your cruising cat. Sprints can be very dangerous because your average will take a significant hit and you are way less likely to monitor your average properly during a sprint than in basically any other situation. So ideally, you won’t have to finish the race with a sprint against another cruiser, but chances are that is something you won’t have much of a say in. You can only keep your fingers crossed.


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Race Report: UK Armed Forces Cycling Community Race Night – How to Cruise London Loop

Time to take up arms against British forces. As they say, “In love and war…” Hence they wouldn’t mind a little cruising, would they?

The course was two laps around the lovely London Loop. I won on ZP but I consider it a botched race as I went over limit slightly and damaged my 90 day ZP average. I might bust out of cat any day now if I’m not careful and keep the gold fever in check.

The London Loop, which includes the climb up Box Hill, is a very interesting, very tricky course for the cruiser. Or to be more precise, it is tricky if you can’t measure a trailing 20 min W/kg average directly (I still can’t) and thus have to rely on guesstimates from 20 min block averages (please refer to lesson 5 of Cheat School if you didn’t understand that sentence). Which would explain why I went over limit at all. I would assume it happened somewhere around the period of 00:10:00–00:30:00.

In fact, I would go as far as to say that legit top cat riders would do well to stay away from the London Loop even though it is a fun course. As a strong legit rider it would be only too easy to go over limits somewhere in the first 20 or 30 min, carried away by sandbaggers and an eagerness to position oneself well before and at the beginning of the first climb.

My guess is that this is a typical course where those about to will get their upgrade. But two laps is not a short race in Zwift standards! Even in cat B you are looking at a 50 min effort, and down in cat D it will be difficult to go under the hour mark. So if you are riding legit and push hard early on (and why wouldn’t you, seeing as you are not a cruiser?) then you might get upgraded for that initial effort while still suffering badly on the last lap at maybe 0.3 W/kg below limit, since by then you are out of both matches and steam, way out of contention against the complimentary sandbaggers and cruisers that your race came stocked with. And the next races you join, you will be assigned gatekeeper for the gruppetto up in the next category. Isn’t it ironic?

The course starts close to the Tower of London, follows the north bank of the Thames westwards and down south, takes Lambeth Bridge over to “Surrey” (yeah well…), up Box Hill, then down and across Tower Bridge and back to the finish arch.

The standard hard start will take you through most of the inner city section. Your group may slow down by or a little before Lambeth Bridge and by that time your average will be quite high. So you are going to have to slow down further if you want to avoid a WKG or an upgrade. This means the early climb will be affected by your need to go under cat limit for the remainder of the first 20 min.

As soon as you finish the first 20 min you can do the post-20 min push. As long as you are not pushing Watts higher than those at the start of the race and since you had to go under limits for a bit towards the end of the first 20 min, you don’t necessarily have to restrain the post-20 min push to cat limit. You can actually go harder. Your trailing average still contains some minutes of under-limit effort and ahead of you there is the descent where you can get some rest and get your average down. At the foot of the descent later on your average will likely be quite a bit below cat limit if you supertucked the descent.

That doesn’t sound so hard, does it? Well, it’s hard to gauge exactly where your peak 20 min period will be. It may not be the first 20 min as is usually the case in most races. To make things worse, if you did well in the climb and managed to drop some riders, it will also be very tempting to create additional separation to safeguard the descent against heavy riders by stomping that last little climb just beyond the KOM portal right before the descent starts. And then once the descent has started you don’t want to slowroll up to supertuck speed, so you stomp it again. Those additional Watt peaks could easily send you through the performance ceiling even though your average may have been OK during the latter part of the Box Hill climb up to the KOM, regardless of whether you are cruising or merely riding legit.

Notice here how the line between cheating and playing fair gets blurred? It’s not you. Or “they” (villains like me). It’s that fucking W/kg cat system that ruins races on such a fun course. But should you, if you ride legit, safeguard against an accidental upgrade surprise here at a point where you don’t feel ready to move up to the next category and get crushed? It’s up to you, but you really shouldn’t have been put in that choice at all. With a results-based cat system you wouldn’t be. Don’t forget, as a legit rider you are going to be toast on the second lap.

Let’s move on. Try get up to speed and into supertuck as soon as you dare in the descent. There are a couple of spots where you may have to pedal a little to not lose precious seconds on the pursuers, but otherwise you can supertuck most of it. Also be prepared as the descent ends and you turn into the train station. It is very easy to lose seconds there as well. Your heart may have broken a smile again after supertucking but your legs may have turned a bit cold and stiff.

Once you have pushed up the steep little escalator climb up to the station entrance – and pushing hard should be fine here – make sure you get up to cruising speed fast on the flat. After that you should be relatively safe until the finish unless chased by a big group or a couple of rhinos.

During the first lap you will want to have wheels to suck post-descent as there are a fair few flat kilometers before you hit Lambeth Bridge the second time around and drag is no longer an issue. And there probably will be wheels nearby. In fact, you will have to weigh the value of any time separation against drafting opportunities already in advance towards the last bit of the first Box Hill climb. It’s too early to attack anyway. First lap is all about positioning for the second lap, where you will make it or break it.

On the second lap, however, only cruisers, sandbaggers and top cats will still be around (by necessity). The field will be much thinner and dispersed. In this run I climbed mostly solo in the second climb and then went on a solo ZP victory from the summit. They never caught me in the descent in spite of my low weight (thank supertuck for that). This is a Pantani or Virenque kind of course where things like that can actually happen.

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Race Report: The Alpe Dash by HERD Racing League – How to Cruise Road to Sky

Road to Sky is by far my easiest cruise. It isn’t a particularly popular cruise, so the races are typically a mix of of just sandbaggers and legits. Further, the heavies only have a very small advantage there. They have the upper hand in the short approach and if they can make clever use of it, then they can get a head start in the climb that may be hard for a lighter rider to bridge without going over limits. But usually they don’t present the normal, often unsurmountable, problem for a cruiser on the lighter side of the scales. Finally, even a stronger cruiser, should you ever meet one on the Alpe, does not have much of an edge since the pace should be set as even as possible for efficiency – as long as you can stay at limit for the entire duration of the race, be it at 100 or 150 BPM, you are competitive. So essentially, when I cruise Road to Sky I expect to win. And I did, this time too.

The start was slow and the front group arrived at the climb a couple of Watts below my set limit average of 190W. Well, not quite the front group. There were three riders ahead, although within eyesight, who I was sure belonged to the sizeable group of sandbaggers that had signed up.

Once we hit the climb I just kept going at the same pace all the way until the finish. Like in the Lutscher CCW race two days earlier, this is a 1 hr+ race in the lower categories, meaning the legits simply can’t keep up. Somehow this course also seems to be way more demoralizing to many participants than the Lutscher. Which is kind of funny to me. Sure, it’s a little bit longer, but it’s way easier on the legs and the heart. You just keep going steady. TT style (unless you, quite unlikely, really need to drop someone). Piece of cake. And again a huge lead on the runner-up. Note that 14 riders got DQ’d or UPG’s, more than actually finished the race within cat limit. People always go too hard in the early climb. And those were just the ones registered on ZP… Like I said, you rarely face skilled cruisers on Road to Sky, playing the German board game known to us as Zwift racing.  And the legits can’t last at 2.5 or 3.2 or whatever W/kg for a race that long. Hence the wide time margin. It has absolutely nothing to do about heroics or physical prowess. It’s just plain cheating, slipping into the blind spots of an idiotic race rule set that should have been reworked years ago.

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Race Report: 3R Climbing Race – How to Cruise Lutscher CCW

Lutscher, especially the counter-clockwise version, presents an interesting challenge for the cruiser who doesn’t fear a climb. It’s much trickier than e.g. Road to Sky, which is a very straightforward climb.

You start in town with a shortish approach to the mountain. Then you go up the steep side. Then you go down the somewhat shallower side. And then up again the steep side toward the finish.

The approach is so short that it isn’t quite critical. Still, you don’t want to fall behind too much at start. So the first challenge is to find a group with a suitable pace to draft behind. You can go a little over limits here but remember that you need to compensate for it later in the first climb during the latter part of the first 20 min. Sandbaggers and inexperienced cruisers will fail to do so and get snuffed out unknowingly already in the first climb, ZP will tell them later.

If you cruise in cats C-D, then the first 20 min block will occur well before reaching the first KOM portal. This means that while you may have to compensate for a hardish start by slowing down in the first climb, a margin below cat limit, then as soon as the race clock hits 00:20:00 you can do the P20P, the post-20 min push. But not only can you suddenly afford to go back up to cat limit in your climb. You can actually really push it and go above limit.

The second 20 min block will end in or close to the descent, where you will aim to reach 58 kph ASAP to start supertucking and basically do 0W as much as possible. However, remember that if you push it too much once the second 20 min block starts, even though the descent will take care of the average for the second 20 min block, your trailing 20 min average cannot quite tolerate a super high effort, in case you cruise well below your true capabilities. So if you had to end the first 20 min block at, say, 0.2-0.3 W/kg below cat limit in the first climb to compensate for the hard start, then you can only push the first part of the next 20 min so hard. In e.g. cat D, you probably shouldn’t average higher than 2.9 W/kg (before the 95% recalculation, so effectively something like 2.8 W/kg).

The third 20 min block, depending on your cruising cat, may involve both the descent, the flattish stretch before the second climb, and the first part of the second climb. The descent is going to make your trailing 20 min average plummet, so you can afford to push after that. It will be up to you whether to start pusing already on the flat, if that makes sense considering the race situation and your rider characteristics. If not, then you hold a little and wait until the climb starts and then begin dropping people.

If you are cruising cat D, then the race will continue into a fourth 20 min block although incomplete. Just be mindful about your trailing average. If you pushed too hard towards the end of the third 20 min block you will have to compensate for it during the finishing minutes, which is far from ideal.

Remember that when cruising lower categories, this is a +60 min race. There is absolutely no way any non-cruiser could keep up with you. By definition their FTP should be 2.5 W/kg or 3.2 W/kg tops. Unless they somehow defy the laws of sports physiology they cannot stay at that level for over an hour, and since the ZP FTP grossly overstates a legit rider’s true FTP, they will not last in the final climb. So the only opponents you will have are cruisers and sandbaggers. Try to tell the difference.

I am going to need several more runs before I can say I have perfected the Lutscher. But it was an OK run. I was caught off-guard by a late entrant that I wasn’t aware of. I was certain (mistakenly) that he wasn’t ZP registered and never worried about him. Being a bit heavier than me and also going slightly over limit, whereas I made damn sure I wouldn’t, he slipped away with quite a margin during the final block. I’m not completely sure I could have beaten him without getting a DQ. Being an ex-cat C rider like me but with a weight advantage he could make better use of the descent and the flat. He was very efficient. Still, I got a silver and am quite content.


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Race Report: Midweek Crit Race Series by SZR – How to Cruise (and Still Lose) Downtown Dolphin

With a slow week in the Build Me Up program for a change, I thought I would add a race, starting in my old cheating pen. I had set my eyes on the new edition of the SZR iTT series the day before, which would have taken me up and down Bologna and then up again on a TT bike. It would have suited me fine at 73 kg and capacity to do the whole race at WKG limit (although admittedly at a rather high HR as things stand now). But things went a little upside down in life and I lost the opportunity. Losers can’t be choosers, so I signed up for the new crit race series the day after instead, knowing full well in advance it would be awfully hard or even impossible to accomplish anything in it.

There’s not much to say about the race really. I went out hard-ish at start, then stayed around cat limit trying to get as much draft as I could with still freakishly high average Watts dropping all too slow, had to drop from groups going at DQ pace a couple of times. And, being a little rusty, in the last minute had to basically stop pedaling in panic to avoid an otherwise inevitable UPG.

Then once we hit 00:20:00 on the race clock I was free to do the… let’s give it a new cool acronym… the P20P, the post-20 min push that I described in lesson 5 of Cheat School. The idea is that the first 20 min of a race is usually the period where your Watts are the highest, especially since the first minutes typically involve unsustainable Watts way beyond cat limit. So the latter part of those 20 min are shaky since you need to get your average Watts down considerably to pay for the early high Watts or you get a DQ. However, as soon as you are out of the first 20 min block, considering the latter part of it was spent clearly below cat limit, you are again free to push hard, at leat up to cat limit again or even higher if you can compensate for it later or if, as in this case, the race will finish somewhere between 20 and 40 min.

Anyway, I gave the P20P a go but didn’t really put my heart into it since the race was obviously already hopelessly lost by then. I ended up 6th but even so only due to primes. Now, the classification is an obvious example of a point I have raised many times before. Heavy riders, relatively speaking, enjoy an advantage in cats B-D. Depending on the scenario, this advantage can even be so huge as to make the race theoretically unbeatable by a light rider. Let’s have a look:

The winner and the runner up went slightly over limit which might screw up their 90-day average. Mr Bronze could roll over the finish line at a comfortable 2.269 W/kg, though, and the reason for this is his weight. The average weight of the top 10 (me included) is over 94 kg, i.e. more than 20 kg on me. There was absolutely no way I could have kept up with the podium in this race. I would have gone over limit by a mile. So with a lineup like this you cannot place well as a light rider in a crit race. It is a mathematical impossibility and you are not allowed to do your best accoring to the rules as doing your best will earn you a DQ. You simply have to hold back and let the heavies win. Crit races are a no-go for light riders. And no, the presence of the Green Cone of Stupidity (Zwift trademark) wouldn’t help here. Sorry.

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I’m back!

No, this wasn’t planned at all. This is what happens when you give honest (sort of) people a covid infection and then give them the idea that doing the Build Me Up program in Zwift is a good way to restore the wreckage the infection left behind. Months pass and suddenly you are uncategorized on ZwiftPower. And can start cheating again! Only I’m not really cheating since I basically now belong in the category I used to cheat in. Thank you, covid!

But in my absence there has been very interesting development in the racing scene in Zwift. Zwift HQ have been busy bees. Let’s go through the key points of the latest development in Zwift racing mechanics, racing standards and the racing community.

It started already in December, where we saw a major update of the software introducing the following changes to the Zwift racing mechanics:

As we moved into the new year Eric Min made an important announcement in the Minterview concerning the future of Zwift racing, where he revealed some important upcoming changes:

The racing community was thrilled, naturally, and the announcement sparked a lot of creativity among community key players, which I would say have led to a structural change since in how races are run. There are a lot of things to say but perhaps it can all be summed up as:

Overjoyed, I set out to write a hommage to Zwift in the form of a musical. I was already half-finished with the score, however, when I suddenly remembered that this musical had in fact already been written. No matter, here it is! Enjoy Zwift Racing the Musical!

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