The Struggle” is the perfect name for the location of this year’s National Hill-Climb Championship. It’s where the best hill climbers from all corners of the country (and also Tom from myWindsock) will gather this Sunday for the final national title race of 2023 in any cycling discipline (we think).
This iconic event unfolds along a challenging 2.67-mile (just over 4km) route in Cumbria. This climb stands out as one of the longer courses for this championship, offering a real test of endurance. The average gradient of the climb is a demanding eight percent, with the steepest part reaching a punishing 24 percent.
The action kicks off just outside the charming town of Ambleside, and the event is masterminded by the Lakes Road Club and Barrow Central Wheelers. For this year’s edition, both the reigning women’s and men’s champions are returning to defend their titles (and Tom from myWindsock will also be trying not to walk up the steep bit).
The segment where the action will take place. For a detailed write up on the course this weekend, have a look here.
In the men’s competition, reigning champion Andrew Feather has made a remarkable recovery from an illness he battled in September and is feeling in top form as he approaches Sunday’s climb. He acknowledges that September was a tough month for him, but his power output is back where it should be.
As the event approaches, Feather is making some last-minute adjustments to his bike this week (every gram helps) and has headed up to Cumbria early to prepare. While he’s uncertain about how he will perform on the day, he recognizes that Ed Laverack is likely the favourite, especially given his specialisation in long climbs. Feather has conducted several course reconnaissance rides and feels well-prepared. He’s determined to give it his all and hopes for the best. The uneven gradient may also suit a rider like Feather who’s shown many times before that he has a rarely matched ability to accelerate on steeper gradients. We have showed that pacing steeper sections harder can save a lot of time and this is something Feather has proved excellent at.
Ed Laverack, who many (including us on balance) are tipping as the pre-race favourite, including the national rankings system on Spindata, is eagerly anticipating the challenge.
The Spindata rankings for hill climbers. I haven’t sifted through the start-list in too much depth but many of these riders will be competing for the top 5 slots.
On the women’s side, Illi Gardner, who rides for Wahoo-Le Col, is back to defend her title. However, she hasn’t had the chance to face her rivals this season, so there’s an air of uncertainty around how the title race will unfold. Gardner acknowledges that while The Struggle’s longer climb plays to her strengths, she’s been working on improving her “punch.” She points out that the National Championship is the first opportunity for competitors scattered across the country to go head to head, making it a bit of an unknown in terms of the competition. Despite the uncertainties, she’s looking forward to the challenge and has been focusing on handling adverse conditions while staying calm and composed. Illi also took the Sa Calobra QOM going under 30 minutes and plenty are saying it’s her race to lose.
myWindsock will be in attendance on Sunday, while I (Tom) won’t be challenging the scoreboard too much, we are looking forward to a great day and will be covering conditions and results on our Instagram story. If you want to plan your effort perfectly, there’s no better place than myWindsock – check it out here.
Marginal gains in the context of cycling refer to the practice of making small, incremental improvements in various aspects of a cyclist’s performance and equipment to gain a competitive advantage. This concept became particularly popular in professional cycling thanks to Team Sky (now Ineos Grenadiers) and their former performance director, Sir Dave Brailsford. The idea is that by focusing on many small improvements, collectively, they can lead to significant overall performance improvements. Since the Sky glory days, we’ve seen performance improvements across a number of endurance sports including cycling, triathlon and running – a large part of this is the accumulation of marginal gains.
A few weekends ago we had the Ironman World Championships in Kona, which was won by Lucy Charles-Barclay in no small part due to how aerodynamic she is (as well as obviously being a great swimmer and runner). Some athletes were less dialled than Lucy, however. We saw road helmets, slow chain choices and sleeveless triathlon suits and it dawned on us that Ironman is probably the sport where marginal gains accumulate the most.
How much difference did 1% make in Kona?
A 1% reduction in cda leads to a performance gain of 15s. This doesn’t mean that 2% automatically means 30s (as you go faster, there are diminishing returns in terms of time) but it’s enough to make a measurable difference on race day. With a world class field athletes can’t afford to leave watts on the table – something Lucy was acutely aware of having come 2nd a number of times.
Aerodynamic testing is a process that takes place over a number of years and the gains accumulate over time. On average, athletes are more aero than they were ten years ago but the distribution of individual athlete’s aerodynamics is similar now with world class triathletes and time trialists somewhere on the spectrum of just muscling their way to results and being perfectly dialled.
We recently wrote about our trip to the wind tunnel here and it’s a practice extremely common with triathletes and cyclists these days. If you want to be competitive in these sports then aerodynamics is something you have to take seriously.
Over the years, the cda of the athletes competing at the pointy end of the race in Kona has dropped. We know this as athletes aren’t actually doing much more, if any, power than they were back in the days of two-piece triathlon suits and those weird triathlon crop tops. We just know now that those (awful) suits also weren’t very fast – among other gains found here and there. We can see how a ‘typical pro’ athlete’s time might drop as their cda goes from 0.3 down to 0.2 on the same day, pushing the same power…
Kona – a generational shift in times
The time in hours drops from over 4.5 to very close to 4. The numbers here are using power numbers regularly seen in Kona and all other conditions kept the same. The accumulation of marginal gains will see the times continue to drop in the next decade too as we aren’t close to the limit of what’s physically possible with aerodynamics on bicycles.
Accumulating gains – a self fulfilling cycle
The other aspect worth considering here, as we see times tumble from one year to the next (myWindsock successfully predicted a Kona course record was coming) is that as riders go faster, they expend less energy. Energy is the integral of power with respect to time. What that means practically is the way you calculate how much energy has been expended is by figuring out how much power was done for how long and adding all of those bits up to get energy. Given that the amount of energy we have access to is the limiting factor in an Ironman, by reducing the amount of time spent on the bike we have more available energy left to run with. This means that athletes can run faster.
To answer our question posed, yes marginal gains still make a difference. Team Sky popularised the concept and Jumbo took it to the next level but the reality of it is that all of us still have unrealised gains and these can really add up. If you want to see how these look on your local time trial or triathlon bike leg, click here.
We take a detailed look at the weather forecast for Kona 2023!
The Ironman World Championships in Kona, Hawaii, represent a pinnacle in the world of ultra endurance sports, marked by distinct challenges related to wind, aerodynamics, heat, and weather. Kona is no ordinary Ironman and conquering the conditions is as big a part of the ultimate outcome as conquering the race distance.
Held annually in October, the event draws elite triathletes who have qualified through a series of global races. Kona serves as an unforgiving testing ground due to its challenging natural conditions. This year, Kona is made more special by being the women’s championships – age group and professional women will take on the island alone for the first time!
The race begins with a 2.4-mile swim in Kailua-Kona Bay, where participants must contend with ocean swells and currents. Year by year, the conditions can be variable in Kailua Bay and the duration of the swim can vary.
The swimming times for women in the Ironman World Championships in Kona can vary widely. The 2.4-mile (3.86 kilometres) swim portion of the race typically takes competitive participants anywhere from around 50 minutes to 1 hour and 20 minutes. Elite professional female triathletes who compete in Kona can complete the swim in the faster end of this range, often finishing in approximately 50 to 60 minutes.
Kona bike course, critics have described it as boring and they might have a point. It’s a barely rolling out and back along a motorway. The wind can provide a bit of spice to the race, however.
Following the swim, competitors run through transition to the bike, covering 112 miles through the island’s somewhat varied terrain. The Queen Ka’ahumanu Highway (Queen-K) exposes cyclists to fierce head and cross winds, significantly impacting their aerodynamics and kit selection. Disc wheels are banned in Kona due to the wind conditions, Ironman clearly not aware that a 90mm front wheel is much twitchier in crosswinds than a disc…
The 26.2-mile run through lava fields and Kailua-Kona, presents an additional set of challenges. The Big Island’s high temperatures and relentless sun introduce a critical element of heat. Athletes grapple with maintaining hydration and minimising heat-induced fatigue, going too hard on the bike could come back to bite you. The Energy Lab section is notorious for its extreme heat, which has seen the end of many a world title challenge.
The weather
We are now on Wednesday at the time of writing and with the race taking place on Saturday we are probably close enough for a decent weather forecast. Let’s take a look at the wind in Kona!
Generally speaking, it will be a relatively cool and calm day (by Kona’s standards).
The BBC weather report also looks similarly mild. Generally speaking, real feel possibly won’t even breach 30 degrees which is relatively rate for races in Kona where heat is usually a huge factor. The temperature and humidity combination is still sufficient to induce overheating in an athlete that has not paced well but it should allow a greater degree in the flexibility of pacing strategies – something athletes might need if they wish to follow Taylor Knibb’s pace on the bike.
Will we see a course record?
All of this points to conditions being relatively fast, and with the best female pro field ever assembled (in my opinion), the racing will be red hot too. The course record sits at 8:26 and was set by Daniella Ryf who is racing on Saturday. Personally, having looked at the data, the field and the weather I think we will see a number of women under 8:30, probably the entire podium at a minimum but there are a number of athletes very closely matched. It doesn’t seem impossible to me based on the wImpact scores on the bike and run that we could see a time under 8:20 win the race – a time that would have beaten Jan Frodeno in 2014!
Partially, this is due to the change in bike tech we’ve seen in the past decade as well as the calendar change leading to lower winds experienced in the past couple of years.
If you want to experience the course preview in a bit more detail – check out myWindsock here to load up your own forecast.
It’s hill climb season and that means our inboxes are full of pacing questions. Most of these questions come from pacing climbs with varying gradients. Everyone knows how to pace a climb that’s a steady gradient – just figure out roughly how hard to go then go that hard. With variations in gradient however, things change. Other forces come into play, many climbs have a flat bit at the bottom and gradually get steeper, others are stepped climbs or may even contain a small descent in the middle. The thing is, with any climb of varying gradient, pacing it evenly is likely not the fastest way to get up it with whatever available energy you have at your disposal. To explain this concept we will jump straight into an example…
A climb with an increasing slope…
Let’s imagine an example where we have a climb with a gradient that increases slowly from flat to completely vertical. At any point on the climb, the forces acting on something ascending this climb (in our case, usually a bike) are…
Yes, we’ve ignored air resistance as this complicates matters. While the physics engine that myWindsock runs on can handle this complication, for now we will make some kind of low speed assumption that allows us to ignore air resistance (though a good rule of thumb is that it becomes more important to think about in hill climbs the faster you go).
The thing for us that’s important is the component of weight acting down the slope – this is the weight that we feel when trying to accelerate the bike up the climb. This component of weight is proportional to the sin of the slope angle. How does the component of weight acting change as that angle increases?
Here we have a plot of the force experienced by a rider due to their weight (with other components of resistance ignored) as the angle of a climb increases. Three system masses are included here to show how these differences are felt on riders with differing masses. The y-axis, labelled “Weight”, shows us the effective weight felt. The angle here goes from zero (completely flat) to 90 degrees (think literal vertical wall). In reality, a 20% gradient is only 11 degrees but the larger angles are shown to emphasise the point. At these lower angles, the proportion of force can be assumed to be linear (at small angles sin(x) is roughly equal to x).
How should I pace then?
Over any given duration, you’ll have some given energy budget (ie, you know can normalise some power for some duration) and this should be your starting point. From here, it’s about thinking where to invest that energy for the biggest return on speed. Generally speaking, this equates to going harder on steep bits as the resistive forces increase with speed at a slower rate when you’re moving slower (due to the exponents in the aerodynamic equation).
In simple language, practical advice would be to change what you’re thinking about based on speed – for flat parts you’re working against air resistance, for moderate you’re working against both air and gravity and for steep you’re working primarily against gravity. Go harder on steep bits, get more aero on flat bits.
Thinking about, and quantifying, these things is far from simple and it’s made easier when you have a physics engine to handle the calculations for you meaning you can focus entirely on preparing yourself for race day – knowing that you’ve used all available data to inform a race plan you can be confident in. If that sounds like your sort of thing – sign up to myWindsock today.
Recently, myWindsock went to a wind tunnel and found out some very interesting things.
myWindsock in action at the tunnel – turning data collected into actionable information for race day!
If you log into myWindsock and open up a forecast, you’ll see a number which is labelled as ‘cda’ – this is your coefficient of drag multiplied by your frontal area. myWindsock, generally speaking, does a pretty good job of estimating your cda from previous rides which you can pop into planned rides to see how fast you might go (when combined with weather forecast data, your weight and other variables).
Recently, I went into the tunnel and, given that I do quite a bit of work here at myWindsock I thought I’d drop Ben a text letting him know I’d be going and he kindly decided to come down. I was quite pleased about this. Who better to provide their opinion on what to do next than the founder of the most democratic virtual wind tunnel available on the market?
The reason I went to the tunnel is because I’m currently in the process of trying to get a pro win under my belt in a middle distance triathlon. The thing is, I’m not particularly physically talented (I’m ok for sure but by no means some kind of freak of nature). This means I need to ride faster without simply pumping out 350W for two hours – enter my aerodynamic era. The first step was to go to the tunnel and measure my cda.
The next two sections explain cda then (simply) how a wind tunnel works. If you already know these things or, alternatively, don’t particularly care and just want to see how much speed we found then scroll past these bits…
What is cda?
CDA, or Coefficient of Drag Area, is a critical concept for cyclists, especially those interested in going faster. It’s a measure of how aerodynamic a cyclist and their equipment (known as a ‘system’) are as they move through the air. Generally speaking a good time triallist’s cda will be around (or lower than) 0.2 – though this can take many trips to the wind tunnel and velodrome to achieve.
Imagine riding a bicycle through the wind. The faster you go, the more the air tries to slow you down.
Here we’ve plotted cda against power requirements for a cyclist riding along a flat road with no wind and no corners just to see how cda impacts the amount of power needed to ride at 40kph. We can see that the relationship is linear (as the cda term in the aerodynamic equation has no exponent) – as cda goes up, so does the required power.
CDA takes into account two key factors:
1. Coefficient of Drag (Cd):
This part represents how “slippery” you and your equipment are to the air. A lower Cd means you’re more aerodynamic, like a sleek, streamlined shape that doesn’t create much resistance. It also means you’re likely wrapped in some kind of aerodynamic material (like a skinsuit) that manipulates the air in ways that reduce drag.
2. Frontal Area (A):
This is the size of the surface area the air hits as you ride. If you crouch low and make yourself as small as possible on the bike, you reduce your frontal area. It’s a measure of what the air ‘sees’ as it approaches you.
CDA is calculated by multiplying Cd and A. So, if you have a low Cd (meaning you’re very aerodynamic) and a small A (you make yourself compact), you’ll have a low CDA, which is great because it means less air resistance, and you can ride faster with less power. Cyclists and engineers often use wind tunnels and computer simulations to find ways to lower their CDA. This can involve using more aerodynamic equipment, adjusting riding positions, or choosing clothing that reduces drag. One thing that’s often surprising is that one thing that tests fast on one rider can test slower on another showing the importance of measuring CDA and not just assuming that aerodynamic gains are the same across all systems.
In competitive cycling, especially time trials and triathlons, having a low CDA is crucial because it can make the difference between winning and losing. Riders strive to strike the right balance between power output and aerodynamics to maximise their speed and efficiency on the bike.
How does a wind tunnel work?
Here we have Ben checking out some of the latest measured tunnel data and looking into how it impacts the time that an athlete takes to cover a 90km Half Ironman course.
A wind tunnel is a clever machine used to test how things, like aeroplanes, cars, or even buildings, respond to moving air. It can also be used as a means of making various objects and people more efficient (think F1 cars and cyclists). Imagine a wind tunnel as a giant tube, kind of like a long, narrow room with powerful fans at one end.
Here’s how the process of measuring in a tunnel works:
1. The Model:
First, scientists or engineers create a small-scale model of the thing they want to test. It could be a miniature aeroplane or a tiny car, for example. Alternatively, the tunnel is big enough (as the one we visited was) to fit a 1:1 size model in there (such as a fully grown cyclist and his bike).
2. The Tunnel:
They place this model inside the wind tunnel, usually near the fan end. The tunnel is designed to be smooth and sleek inside to make the air flow nicely. This means the only disruption to the flow is caused by the subject of the test.
3. Air Flow:
Now, here comes the exciting part. The fans at one end of the tunnel start blowing air super-fast (or not, depending on what you’re testing) down the tube. This air simulates the wind that the real thing would experience when it moves.
4. Testing:
As the air rushes over the model, sensors and cameras record all sorts of data. They measure how much force the air exerts on the model, how the air pressure changes, and even how the air flows around it. In the specific case of a cyclist, there are cameras to ensure the same position is being held by the rider to ensure changes made are isolated and any differences in measured CDA are due to the target change and not some accidental positional change.
5. Analysis:
Scientists (or Tom, Ben and Andy) analyse this data to understand how the real thing would behave in different wind conditions. They can tweak the model or make changes to improve its performance or safety. This is where myWindsock came into its own for our analysis – as a means of putting the cda number into context we plugged the measured value from the tunnel into a myWindsock forecast of the target event to see how the changes in cda impact the overall time of my target race with the pacing plan input into the forecast.
6. Repeat:
The test can be run many times, changing the wind speed or direction to see how the model responds in different scenarios.
In the end, a wind tunnel helps engineers make sure that aeroplanes fly smoothly, cars are fuel-efficient, and average triathletes can cycle fast. It’s a real aero-nerd’s science playground where we can learn how things interact with the air.
What did we learn in the Wind Tunnel?
The first thing that we learned was that speed matters. What’s fastest at 35 kph isn’t necessarily fastest at 45 kph. This is particularly important for my case as I’m racing a triathlon where the speeds are slightly slower for a couple of reasons – the primary one being that the finish line is not where the bike course ends… We had a couple of runs and suspicions of things that have tested faster at higher speeds but at “triathlon speeds” were actually slower.
What looks aero isn’t always aero
We ran a poll on Instagram and found that everyone thought the right hand side run was faster than the left. On the left, we have my original bike fit position with a water bladder down the front and on the right, the bladder is still there but with the saddle back, head down and arms out slightly – a position that was a bit slower.
Other than the fact that the left hand side position was faster, it was also more sustainable (for now, though these things are trainable). The run on the left had a cda (at 40kph) of 0.239, the run on the right had a cda of 0.249.
Over the race course, this change in cda is worth half a kph – a significant saving especially considering that the position is much more comfortable.
We can see how much of a difference this makes, over 90s for the same power during the course. This can be combined with the fact that the position on the left hand side is easier to run off as well, being less muscularly strenuous.
Stuffing your drink down your top can make you faster
Anyone who’s done a triathlon will know of the difficulty that various hydration systems can come with. Bottles mounted behind the saddle are prone to launching themselves out of their cages with the slightest bump. Recently, it’s become fashionable to shove a Camelbak water bladder down the front of your suit – primarily for aerodynamic reasons but it’s also quite a convenient place to keep your nutrition.
This caused a big change in cda – we will go into more depth on the bottle data in a future blog as it’s something many triathletes and time trialists are interested in – but it was around a 6.5% reduction on drag with a bladder compared to baseline.
Knowing your cda can help you plan
Relatively small changes in cda over long distances can be worth minutes. When you add these time changes up it can change the amount of sustainable power as well as nutritional planning. The reality is, combining aero data that’s been measured with the processing power of myWindsock is a valuable tool for any athlete and there’s no doubt that all the top contenders are doing this.
In 2023 the National Hill Climb championships are being held on “The Struggle” – an iconic British climb.
The climb is 4.31km at 8.4% and gains 364m of elevation but it’s not an even 8.4% (to be honest, that wouldn’t be much of a struggle…) – it gets very steep at the top. A climb with uneven gradients becomes an interesting pacing challenge for a rider time trialing to the top.
This blog isn’t a preview of the national champs, but more of a lesson in how you might want to pace the effort. For our purposes today, we will assume a 70kg rider with the ability to average around 400W for the duration of the climb, also as this is a hill climb let’s assume our rider’s bike plus kit weighs 6.5kg giving us a system mass of 76.5kg.
A brief note on aerodynamics
The average speed for a rider doing 400W as a perfectly smooth effort up this climb is high enough for aerodynamics to play a small but not insignificant role – accounting for roughly 10% of resistive forces. A reduction in cda from 0.4 to 0.3 is worth 16 seconds under these conditions and a further reduction to 0.2 (essentially a time trial position would be required for this) is worth another 20s. For today, we will set the cda of our rider to be 0.3, which is a rough assumption as hands on the hoods with slightly bent elbows.
Test run 1: A perfectly smooth effort
I know we do this on almost every blog at the moment but optimising the power distribution over a course can lead to significant time savings.
With a VI of 0 (NP/averageWatts) we can see that this effort is perfectly smoothly paced. Notice also the Wind Penalty is minus ten seconds, telling us that we have a slight tailwind. A brief nod to the hill climb nationals would not be amiss here, if the wind picks up during the day, it’s big enough to make a measure-able difference on a climb of this length.
Using the gradient distribution to set some pacing rules
One neat feature of myWindsock is the ability to view the gradient breakdown of a course. During a climb this is particularly interesting as we can see how much the gradient is lying to us – ie how true is the 8.4% average to reality? Let’s take a look…
All of a sudden, the story of this climb looks very different. In that order, let’s make a new plan based on gradients with a general rule of the steeper it goes, the harder we go but let’s not deviate more than 100W from our planned average of 400W for the climb.
As with any pacing plan, it has to be realistically implementable thus our rules should be simple. Let’s say that anything less than 6%, we ride at 300W, anything from 6-12% we ride at 400W and anything above this we ride at 450W… What does this do to our average power and the average time for the ride?
Ok, so we can see this pacing strategy results in a power that’s slightly too hard so we need to find a way of reducing our power by 24W. That said, the combination of the pacing strategy and the increased power is worth 46s in total time. Notice how the average speed increase has reduced the total impact of the tailwind as the relative wind speed is lower.
Now we need to find a means of reducing our average power, one way might be to get aero as the speed increases. Let’s tuck down above to 20kph and reduce our cda to 0.25, this saves another 7 seconds giving us the ability to reduce the power in other sections. Reducing our flat power to 200W (essentially a brief recovery ¾ of the way up the climb) we can get that average power down to 414W. Finally, we further reduce the power on the flatter sections…
This simulation comes from a more even pacing distribution, a fast start to get up to speed then 200W when the gradient is below 6%, between 6 and 12 we ride at 350W and then full punch at 460W when above 12%. The other change is the reduction in cda to 0.25 when the speed is 25kph or above. With an extra watt, we’ve saved 17s of time!
It’s hill climb season and tiny margins matter. Yes, differences in strategy based on pacing may only be worth 17s on a thirteen minute effort but this is enough to make the difference. If you’re already doing all the other marginal gains, myWindsock can make the difference between first and tenth! Sign up here today.
Cycling and triathlon are both demand driven sports. This means that an athlete’s performance is down to being able to meet the demands of the day. Sometimes, figuring out exactly what these demands are can be difficult. If you want to execute a ride, be that a ten mile TT or an Ironman bike leg, in a specific time then you’ll need to have a good idea of what the demands for that are on a particular course. Obviously, we recommend using myWindsock for this.
A demand driven approach is quite a simple one. You identify a goal, figure out what’s needed to achieve that goal and then prepare specifically to meet those demands. It’s a means of identifying gaps in your performance profile that are limiting your performance and broadly is how world class coaches and performance engineers approach problems. For example, it’s easy to say you want to run a race, ride a TT course or something in a given time but actually breaking down that goal into trainable components and addressing these specifically is how you’re likely to achieve it.
With anything, analytics tools are useful for this. We would put myWindsock in the same category as something like Training Peaks, WKO5 or a lactate test with regards to its usefulness from a performance perspective. We don’t focus on physiology, but a good performance in cycling (especially a time trial situation) relies on maximising the ratio of energy in to energy out. Your physiology is your physiology and come race day you’re unlikely to suddenly crank out fifty more watts than you’ve managed in training but you can certainly maximise the power that you have available with aerodynamic testing and optimised pacing.
A demand driven approach to a race
I’ll use a race that I’m planning to race as an example of this. It’s a middle distance triathlon in Ibiza and the bike leg is around 90 km with roughly 900 m of elevation. In order to remain competitive I’ll need to be off the bike in under 2 hours and 10 minutes having used as little energy as possible. I’ve got around 300W at my disposal (while still being able to cobble together a decent run) for this so we will have to take that into account.
The race route runs the length of Ibiza and is not flat. It is 90km with around 900m of elevation – a course that is described as ‘rolling’ by the organisers.
Let’s start with a power budget of 310W which we will cap as my normalised power upper limit, while I know that I’m capable of more than this – one demand of a triathlon is that you have to go running after the bike leg and in order to execute this run well, keeping the ride as close to the first lactate threshold as possible is optimal.
As we can see, the goal discussed below is reasonable with a completely smooth application of 310W. We have discussed in the past how this is not a particularly efficient means of applying power during a bike course.
Given the goal is to execute a bike leg under 2 hours and 10 minutes, this ‘smooth power’ input serves a sanity check as to whether or not this goal is actually achievable. From this, it seems likely that this is the case so let’s optimise the pacing strategy within the performance constraint that we’ve identified.
The first step to this is check where on the course over-pacing climbs makes a difference. We do this with the “where power matters most” feature on myWindsock.
This plot, under experiments, shows us where on the course that an increased application of power will provide a greater return on investment for speed. This will be familiar with many experienced time trialists as it shows us steeper sections, brows of hills and headwind sections.
Now, we simplify the breakdown of where power matters most and implement this as rules.
As the road tilts up, I will ride at threshold. If we really slow down, I’ll ride at 400W. It’s important that any pacing plan is simple and easy to implement. On top of this, I will also ride in zone 2 above 50kph and stop pedalling over 60. This is not ideal for a straight TT but in triathlon, conserving energy for the run is very important.
We can see here that for a lower average power, we can go a couple of minutes quicker than the previous 2:09 with the smooth power. Playing around with different pacing strategies we can see changes in outcome time.
It’s better to pace climbs slightly harder than flat sections (which you can read about here on our blog) and given we know what power we can manage for given durations we can come up with a training session to help prepare the specific demands of the course. Using myWindsock’s rules feature we can figure out how we will pace these climbs, build an interval session and plug it into Training Peaks for all or part of the course. This means we can train for the specific demands of race day on the turbo trainer at home.
World class athletes and coaches all use a demand driven approach to competition. Setting a goal and achieving it requires an approach that identifies the things that are currently preventing that. myWindsock is a tool for this, one of many and one used by Olympic Gold Medalists, professional cyclists and teams as well as the UK’s best time trialists.
Sepp Kuss is currently in red going into the TT on stage 10 of La Vuelta. It’s a bit strange, no one expected him to be in the race lead but – if he can get through tomorrow, he has the class in the mountains to win GC. Remco is 2:22 down on the American with Kuss’ Jumbo team mates, Roglic and Vingegaard on 2:29 and 2:33 respectively.
The TT is only 25.8km in length so, while we all expect these gaps to close, the chances are Kuss will still be in the race lead unless Marc Soler or Lenny Martinez pull a really great TT out the bag. Sepp Kuss’ time trial ability has rarely been tested in the past but we all know that Jumbo can execute a good TT when they want to.
The time trial is only 25km long but we saw in this year’s Tour de France that short time trials can create big gaps but this time trial is, for all purposes, completely flat. This both benefits Sepp Kuss and hinders him. The benefit comes from the fact that not much time can be lost during a medium length flat TT as the speeds are high, however relative to the rest of the GC contenders Kuss is one of the better climbers – and his TT ability remains unknown…
Two things of note come up when thinking of this course, firstly it is basically pan flat and secondly there are a few technical sections. This time trial is essentially a test of watts and cda though – you’ll see riders who have spent time in the wind tunnel will have a big advantage – but more on that later. The main takeaway here is that the course is relatively simple and suits the pure TT specialists.
The race conditions are also relatively trouble free. Here we’ve put some numbers in to represent your ‘average’ grand tour rider and you’ll notice that the ground speed is extremely high for this power. These high speed conditions will suit Remco Evenepoel over his GC rivals and it will also suit Ganna for the stage win. The conditions remain favourable throughout the day and are quite stable seeing no shift greater than a couple of seconds due to weather. That said, this could be the time separating stage winners – look out for that in our Vuelta TT Review.
This plot shows us the effective wind that riders will feel during the course of their TT. These extremely shallow yaw angles show us that a rider will feel the wind mostly on their front and back. This is a relatively simple wind direction distribution and will suit the GC riders that haven’t done a great deal of testing or are experienced time trialists. Simply put, there’s less to be gained by knowing which wheel is fastest in crosswinds vs headwinds which is knowledge some teams will have that others don’t. These simple conditions equalise the TT somewhat.
While this course is flat, there are parts of it where power will matter more than others. There’s a few steep ramps at 3km and just before 6km. The orange bars on this plot show us where inputting a decent amount of power will have the most return on investment. The most interesting instance is the orange bar just before 8km. This is a portion of descent that flattens out and pushing hard on this section before the road drops down again is an energy investment that leads to more speed being held on the lower part of the descent.
CdA and Time
Other than Jumbo and Sepp Kuss, I don’t think anyone knows if he’s spent any time in the wind tunnel. I’d imagine some rudimentary testing has been done but the question of how aero Sepp Kuss actually is seems to be a little bit of a mystery. Apparently, he’s 61kg with an FTP of 383W (this might be nonsense though, I just found it reported online somewhere) but let’s put these numbers into myWindsock and see how varying the cda impacts the time.
It’s clear that aerodynamics makes a huge difference on this course with time spent in the wind tunnel being worth almost two minutes on this course. Sepp Kuss will hope that he’s aero enough to maintain his position on GC. It’s clear he has the power to do a great time trial though. Aerodynamics won’t be a priority for Kuss who primarily rides as a mountain domestique so his time will depend on two factors – how aero he naturally is and how fast Jumbo’s equipment is.
Remco vs Ganna
As well as the GC drama there’s the prospect of a stage win up for grabs. Let’s estimate some times for Remco Evenepoel and Pippo Ganna to see who will come out on top using what we think we know about their various numbers.
Remco’s predicted time is on the bottom, Ganna’s on the top. These numbers are estimates and the time prediction can of course change with the weather but we notice two things – Ganna’s weather is marginally more advantageous and the course suits him slightly better. The official myWindsock prediction is that Ganna will win the stage… just.
Working out whether or not crosswinds will produce echelons is a key part of any cycling enthusiast’s arsenal of skills. It allows you to answer the vital question – should I bother watching this or just catch up on GCN? myWindsock, as per, has the answer! That said, it’s the sort of thing that is a little easier with a bit of knowledge – though one day myWindsock might have a feature that delves into crosswind likelihood in bunch races… perhaps.
Under what conditions do crosswinds cause echelons? Luckily, in 2021 someone did a study…
In crosswind scenarios, road cyclists encounter additional air resistance and a destabilising sideways force. Under such conditions, a collective of cyclists adeptly adjusts their positioning to mitigate these forces by forming an echelon. This echelon formation involves a diagonal single-file line of riders positioned diagonally across the road. This contrasts distinctly with the arrangements chosen in wind-free environments.
To scrutinise the impact of crosswinds on the drag and lateral forces experienced by cyclists, we conducted wind-tunnel trials using a scaled-down model of a cyclist. By employing a load cell, we accurately measured the exerted forces. Various configurations were explored, involving one, two, and four cyclists, with alterations in yaw angles.
The findings reveal that in a fundamental arrangement featuring four riders at a yaw angle of 50 degrees, a sheltered cyclist within the echelon encounters less than 30% of the air resistance experienced by the cyclist positioned outside the echelon, who struggles against the crosswind along the roadside. Moreover, we demonstrate that the adoption of an echelon formation in crosswind conditions becomes advantageous only when the yaw angle surpasses 30 degrees. At this critical angle, the air resistance on the exposed cyclist increases twofold when the gap to the leading group expands from 10 cm to 1 m (on a real scale).
These outcomes hold substantial implications for devising strategies in road cycling races. They also highlight specific configurations worthy of deeper investigation through more intricate experiments.
The main key takeaway here is this:
The study identifies that the echelon formation is most beneficial when the crosswind’s yaw angle exceeds 30 degrees. Beyond this threshold, the benefits of reduced air resistance are prominent.
How can myWindsock help us then?
We have recently added a host of stage races to myWindsock including all the grand tours, just head to planner and hit “La Vuelta” (the grand tour that’s on at the time of writing) and you’ll see all the stages ready to load into the planner. We originally did this to help journalists and teams out with pre stage analysis but it’s also a handy feature which tells the viewer whether or not they should bother watching.
In fact, as I write this now I have the Vuelta on and a rider from some random continental team is on a hopeless solo break while the peloton enjoys a coffee ride behind him. The key lies in the Yaw Distribution plot…
Load the race of your choice into myWindsock’s planner, if it’s not available directly on our site or app then you’ll probably be able to find one from the organisers.
Open the route and set the speed to something roughly similar to the race.
Open up the yaw distribution plot…
This tells us the number of minutes across the route where the yaw angle exceeds various points – it’s set into bins.
A rough rule of thumb would be if the total time above 25 degrees of yaw exceeds 30 minutes, something might happen…
Let’s check today’s Vuelta stage…
The stage in question, a pan flat ‘boring’ stage but that wind flowing off the coast might cause something to happen…
This is the yaw angle distribution plot. This is what we might describe as a ‘typical’ day with yaw angles focussed around zero to ten degrees. It’s unfortunate today that it seems this particular stage will be a bit of a snooze fest however – echelons seem unlikely. For something interesting to happen we would be looking for a lump around 25 to 35 degrees of yaw or perhaps an even distribution of yaw angles which would simply tell us it was blowing strongly all day.
Yaw angle tells us the ‘effective’ wind angle, it’s the wind we feel when riding rather than the wind blowing on a stationary object. myWindsock has all sorts of features like this which will have you lining up at the start of your next race, chaingang or group ride more informed than any other rider – sign up here.
The national 25 is almost upon us. The best time trialists in Britain will gather in Scotland to unleash their watts onto the WE25/03. With CTT providing such a helpful course description, we thought this preview might be an opportunity to check out the advantages that can be gained from using myWindsock to check out the course relative to your rivals who only check CTT.
The good people at Cycling Time Trials put together a course description, elevation map and GPX file for the good majority of open events hosted there. It looks something like this…
CTT Course Description
Start on the A926 west of Forfar Academy, proceed west to join A90 southbound to leave the A90 at the Forfar south exit signed A94, take the 1st exit at the roundabout to go under the A90, take the 1st exit at the next roundabout to rejoin the A90 northbound to leave at the Brechin south exit signed A935 to take the 2nd exit at the roundabout to rejoin the A90 southbound to proceed to the second Forfar exit signed Forfar and Kirriemuir A926 to take the 2nd exit at the roundabout to finish on the A926 heading towards Forfar shortly after.
It’s comprehensive, for sure. I can even imagine the readers and riders thinking, who on earth would I need myWindsock? I have all of this information for free on CTT?
Let’s check the course out with myWindsock and see what insights we can gain…
For the purpose of today, we will avoid weather related chat. For up to day information on conditions from the best provider of cycling weather information you can either follow us on Instagram, where our story will be updated regularly in the 48 hours leading into the event or check the forecast out here yourself. For all insight and analysis available, sign up to myWindsock here.
The most interesting feature on this course is the 219m of elevation gain, not hilly by any stretch but considerably rolling for what is essentially an out and back along the A90. This will require riders to pace the effort more efficiently if they’re looking to win. This is not a course that can simply be settled as a watts per cda contest. It’s plausible that a rider that is less aero and less powerful could beat a rider more so simply due to pacing. The climbing is one factor, the gradient distribution is another, the vast majority of the climbing is done between 0 and 3 percent. Check out myWindsock’s gradient distribution plot below…
The gradients are primarily shallow with almost all of them being less than 6%. This is a course that should be ridden in the aero bars whenever possible. It’s still the case that on shallow climbs the majority of the work is being done against air resistance.
Roughly 15% (though this number will change rider to rider) of the work done on this course is done against gravity. This means, for a rider averaging 300W across the course, 45 of those watts will be used to overcome the elevation gain. That’s not insignificant by any stretch – this said, most of the climbing done is at relatively high speeds so this course might suit lighter riders that climb well in the aero bars. There’s definitely a more significant watts per kg component than we usually see in a time trial along an A-Road.
Where power matters most
myWindsock premium users can see highlighted sections of the course where power output has an outsized effect on speed. These sections are usually the steepest parts of climbs but can also be accelerating out of sharp corners.
Rolling time trials like this require a slightly different approach to pacing than a flatter TT – the most efficient effort physically is not the most efficient effort physiologically and you can go faster for less watts by focussing the power in the right place. For more generic advice on pacing a hilly time trial, check out myWindsock’s blog on this and also using rules as a pacing tool. In order to be the most informed and best prepared rider on the startlist, check out myWindsock here.
UK Time Trial Events
