For those who still are not understanding why trainer difficulty is not "like gearing" here is a scenario with some additional specificity that may clarify things: Let's say for instance you it a 15% grade, challenging for most mere mortals, at 100% difficulty you will face that with all the resistance commensurate with that gradient. It will be very difficult and you will have to use likely a very easy gear to apply power to the pedals. Let's say a 50-32 gear ratio for the sake of argument. There is a minimum amount of power that is going to be required to overcome that resistance and if you are incapable of producing that power, you will not be able to move the pedals. Now, let's say you reduced the difficulty to 50%, now you've halved the resistance and can very likely move the pedals because your power is sufficient to do so. Zwift will allow your avatar to move up the road based on that calculation, however, in reality, you likely would be stopped on the side of the road in the real world because your power/torque capacity does not meet the inertial requirements to move the bicycle. The slider is making the hill easier while applying your actual output of power to calculate virtual speed. Moreover, the trainer difficulty slider affects the descents as well allowing one to continue to apply power in areas that they very likely would spin out. This again is calculated and will produce a speed benefit that would not be possible in the real world or at 100% trainer difficulty. The slider isn't gearing, it's realism effect.
All I’m hearing is that for the last year and a half I have been living a lie and my 47 minutes up alpe du zwift with 325w average on the segment ain’t worth shit. Guess I have to start all over again on max difficulty.
@@mrnobody9821 @Mr Nobody how do you come to that conclusion from a comment that explains why its not the same as gearing? If you"re capable of the output then you"re capable. It might feel a bit more hellish at a lower cadence with low inertia. This example was outlining that power that might be insufficient to clear the grade in the real world would still move an avatar in Zwift, someone clearing the alpe under 50 minutes doesn't fall into that bucket.
@@EverythingIsPhotogenic Zwift is 100% about perception. (PERCEIVED effort @ 100% difficulty in the virtual world is intended to mimic ACTUAL effort in the real world.) With regard to climbing, reducing trainer difficulty is EXACTLY the same perception as adding gearing. Given gearing that would allow Mr. Nobody to maintain the same cadence /power that he produces in Zwift @ 50% difficulty, he would climb L'Alpe de' Huez at the same speed in the actual world. (Wind and rolling resistance not withstanding.) That holds true whether you're doing it in 50 minutes or 100.
@@jeffmorgan5152 that's inaccurate. If you want to understand why, you can watch my video on why it's not virtual gearing. And it's not perception. I invite you to read the discussion in the pinned comment as well
@@EverythingIsPhotogenic No, it just suggests that gears larger than 50 / 32 would be necessary to accomplish the task. You can accomplish the same thing by EITHER reducing difficulty or increasing gearing, hence the reference to PERCEPTION. (I'm not challenging your math, but decreasing difficulty or swapping standard for compact chainrings accomplishes the same thing from a rider experience perspective.) For example by way of personal practical application: I normally ride at 100%. When focused on Z2 training in Zwift, I can either restrict riding to less challenging routes, swap out gearing to allow a reasonble cadence when climbing, or simply back resistance down to allow the same thing. VenTop for example goes from off the menu to a favorite sustained effort.
You have a gift. It can be a rare thing indeed that a very smart person can explain a complex topic in relatively simple terms that those with lesser levels of understanding can grasp and apply. This video is a great example of such a rarity. In college, my metaphysics professor Van Hook said something that stayed with me to age 65: “if you cannot explain it, you don’t really know it.” Well done professor!
Not everyone is a 25-year-old racer. I'm a 67 year-old, 190 lbs, Zwift user who has been cycling for 60 years. There are long climbs on Zwift that I want to ride but my knees can't take the long-term stress. So I adjust the difficulty. When riding on flatter routes, I go back to 100%. For me, adjusting the difficulty has made Zwift a better training tool
My trainer bike is a 9-speed. And because of that the gaps with the standard cassette had big gaps. I replaced it with a 14-25T. I would NEVER put my old knees through that gearing outdoors. So, I have to set Zwift difficulty to save my knees. No crazy low cadence stress on my knees. Good that the video confirms my instincts.
Excellent explanation; it reinforces what I kinda already understood. In other words, your video gives me confidence that I understand the purpose and application of Trainer Difficulty. You covered my use case... injury. I have a worn out hip that will eventually need to be replaced. Of course I am in no rush to go thru this procedure. The injury is from years of running; I can’t run anymore but I can cycle. I live in flatland and riding outside is... flat. On Zwift I want to experience the various routes/terrains and I could not do many of the climbing routes without the Trainer Difficulty reduced. If I did use 100% I’d have to ride once and recover for a week or maybe even longer. Trainer Difficulty reduced keeps me on the bike and out of the hospital (for now). Thank you for your time; your videos are always spot on.
Great explanation. But I found out that if you get your cadence in the same region as you would normally do, you still have to change gears in 50% as much as in 100 %, but you use bigger gears. The wattage I can produce are the same in both settings with the same cadence but the trainer is just spinnig faster since the gear ratio is different. The problem you describe gets real in the zone where you are grinding in the smallest gear and can’t spin up to those higher revs. This is were it gets easier on your legs when you move the difficulty lower since you are than able to use higher cadence.
Really enjoyed your video talking about this. I've always wanted my difficulty set to 100% but you make some good points about gearing and injury....I went through a month of knee strain and can totally see a use there. Thanks again!
Great video! Well explained. I'm just not sure why there is so much debate. Anyone who has ridden a bike up a long, steep hill knows that you lose your legs faster grinding at 50 rpm than spinning at 85 rpm. The one issue I have with the settings is I feel MAX difficulty makes it feel harder than real world. I have no problem getting up 10 - 15% grades in the real world with the gearing I have on my bike. I can barely push the pedals over on the same type of grade in my lowest gear on Zwift. I'm not going to buy a different cassette when it works just fine for real-world riding; which is 80% of my cycling.
I found the same thing on an old Elite RealAxiom CT trainer (a USB model even older than the bluetooth RealAxiom B+ model). With trainer difficulty on max, I learned over a few weeks to adjust my weight to about 55% to match VAM (vertical ascent in meters/hr) as reported in Strava for Zwift and real world. Changed to a Wahoo Kickr 2017, kept difficulty on max, put my weight back to my real weight, went for one ride, and the Zwift and real-world VAMs were a match.
Im glad somebody actually picked up, that sometimes zwift is just to ride and have fun. Sometiems you might want to get on small races, even if your knees can go very fast, but cant stand a lot of pressure. This makes it actually fun, and allows you to maintain therapy or just "body maintenance" .
Good explanation. I was really impressed with difficulty at 100%, it really felt like an actual 12% gradient. Anyone who has ridden steep gradients in the real world will understand the difference. I use 100% for training and 30% for racing lol.
I incidentally learned of this setting just a week ago watching another video. I live in a hilly area and climb regularly (no choice, really) and found this setting definitely explains why it felt easier in-game. This video does a better job explaining it than anything else I found online - certainly better than on Zwift.
I've been bicycling for about 5 years, but have only started gradually pushing myself for the past 3 years. In the summer, I ride about 250 to 300 miles a month. I bought an indoor trainer because I live in Michigan and it's just to cold and quite frankly, unsafe to road ride in the winter. Seems like every year I've gotta restart from square one to get back in shape. As a newbie who just purchased an indoor trainer (Wahoo Kickr), I'm still learning Zwift and didn't even know there was a difficulty setting until after using Zwift for about 3 weeks. My first rides on the flat route were crazy difficult by comparison to my normal rides. I ride on some pretty hilly roads and at 100%, it was definitely more difficult than riding outside. My setting was at 100% by default. I didn't even know it. I had no idea how the setting worked, so I turned it down to 50%. To me, 50% actually felt more true to my usual ride experience. 100% was just over the top. My goal is to gradually push it up each month. Last week I moved it up a notch to what I'd guess is 60%? There's no associated number given so I don't know for sure. But my goal is to just keep progressing back to a higher difficulty each month.
Thanks for taking the time to break this down for us this clearly. 100% trainer difficulty for me, though. GFNY coming up in a few months and I need as much help in my uphill training... no real hills in Chicago 😉
Hi Sarah! Your viedos about Zwift are just about everything you need to know about Zwift. I completely understand how things work in Zwift when watching your videos. Keep up the good work! /Pär from Sweden
Very informative. Very new to Zwift but been cycling for over 60 years. I know realise why hill climbing seemed a lot easier than in real life and how to make it more realistic. With age I have found my hill climbing much more difficult if only I could adjust the gradient in real life!!
If you're lowering the training difficulty (reducing the resistence) and flattening the climbs you are essentially just going for a ride on the flat, it's pretty simple .. the watts are measured by the pressure on the pedals from your effort but if there's no resistance you're not simulating riding a climb you're riding a timetrial, you might aswell ride fuego flats ignore the speed and just ride on rpm and power, it'll be the same effort and tension on your muscle groups... Great vid BTW 👌
You would be surprised at how many people do not understand the distinction between gearing and the resistance bias. I think many folks eventually come around with some experience and experimentation, but this tends to be a pretty controversial topic... thanks for checking this one out!
Wow what an excellent thorough video and how all this really works. I couldn't wrap my head around it but you have explained it perfectly thanks so much!!
Very informative. I'm recovering from an injury and can only spin with little resistance. Playing with the difficulty is just what i need to keep me on Swift. Thanks!
Only just starting Zwifting last week. I did the KOM with the radio tower climb on the Tour of Watopia a few days ago not knowing what I was getting into. Even at 50% difficulty I was toast. Felt like such a massive achievement just getting to the top. Now I know it should've been twice as hard! People are machines
I'm a newer sub and wanna say thx for you knowledge and experience with riding and zwift. I just setup my Saris M2 trainer yesterday and am binge watching alot if your videos to really get a grasp of Zwift. I've done a ride to get the feel of it and want to know where to start ie: settings, FTP test, just getting to know how best to approach the platform. What would you do etc. Sometimes I get overloaded with to much info and kinda want a general direction from square one. Hope I'm not asking too much, thanks alot, in the meantime I'm just f'ing around with getting to know the landscape🙂
Hey. Great info about trainer difficulty. Thanks. Very clear and precize explenation. One remark: power is equal to TORQUE x ANGULAR_VELOCITY (P = F x R x ω), here ω is angular belocity of the crank. R is of course constant, you can not change it. F is the average force you press on one pedal times 2. Now, everything is said and all conclusions are totaly clear. The only extra information you need to have is that the level of difficulty set in game corresponds to the slope inclination expressed in % ( which is equel to sin(α ), where α is an angle of the inclination).
Thank you for this video. I'm fairly new to turbo trainers and Zwift and i have only just discovered your channel on TH-cam. I loved the content. It back up my understanding - I have my TD set at 90% as my indoor trg bike has a 34/29 easy gear whereas my IRL bike has a 34/32 gear so hopefully the adjustment will better reflect my IRL experience (though without the weather or the cafes).
This! I just had to switch my indoor trainer cassette from 11-32 to 11-28 so my lowest possible gear is now 34/28 and IRL the lowest gear option I have is 35/33. I moved the TD slider to 90% and hopefully that should help me maintain a similar cadence as I do IRL
Very good explanations in this video. Going the same speed no matter the Trainer Difficulty holds true IF you put out the same watts (this has been proven). But in reality this may not be how it goes for you. On a steep/long hill you may not have the gearing or leg strength to maintain the cadence to achieve those watts (this was touched on in the video). So your watts will drop and you will go slower. But if you lower the difficulty and can maintain the same watts you would go faster.
I like teh idea, "zwift is to have fun, to get you rolling". It also gives you teh option to be a "profesional trainer". It ahs a lot of "elasticity" to fit the users needs. Some of us want to (and are able) to go up to 1000 watts, some of us canot, but still want to "play". It is a program geared to the users needs. LOVE IT !!!!
Thanks for this. New to zwift and was trying to wrap my head around this very thing in the software that I didn't know existed. I knew I had a question, but didn't know what it was. So now I know the question and the answer. 😉
Trainer difficulty allows you to stay in your comfortable cadence/torque window. This allows one to be more efficient on very steep climbs with typical road bike gearing. In real world you cannot trade of gradient for distance. Difficulty is like zig zagging up a hill.
As a 110 kg newbie zwift cyclist I will definitely be lowering that setting just to have a chance to get up alpes du zwift, as I loose weight I will turn it up
This was a really good explanation ... awesome vid. I know when I come to this channel to get some info I really don't need to look any further. The explanations is done in a easy to understand and comprehensive way
Thank you for this video. After watching this I decided to bump up this setting tonight. I was able to keep up the same pace with a higher wattage output. I'm going to try to keep bumping up this setting.
👍 I set my preferred 'Trainer difficulty' according to how I can do the Radio Tower climb. Then youll be able to climb everything within your gearing in Zwift.
Great video! I've been Zwifting for 2 weeks now and I only have a 2x9 speed bike. My bike has a 25-13 cassette in the back which is HARD when it comes to climbing. I have it set at 50% until I can upgrade to a 2x11. Thanks!
Agree'd, watts aren't all created equal. 300 watts at 60 rpm 300 watts at 95 rpm. It's sustainability of watts, and those who argue otherwise don't understand the difference between slow and fast twitch muscle fibers or understand the difference between cardiovascular and muscular fatigue.
Hmm. Watts are created equal. A watt is a measurement of work produced. You are confusing Torque with power. Torque is what you feel when cadence drops. That is you need to produce more torque to produce the same watts at a lower cadence.
@@ttpgsc Watts are a measurement of Power, hence why power meters are measured in Watts. Power is created by Torque. Power can be created with high torque, or low torque, defined by cadence. Therefore, not all watts are CREATED equal.
@@Auntybob the bottom line is that it’s your body that has to come up with the power. Whether someone’s body is better at grinding or spinning is besides the point. Either person can come up with the 300 watts. Watts are watts regardless of where it gets produced. No two people will create those watts in the same way so not sure why you point out the source of creation as being significant.
Basically Zwift should have a tooltip explaining this. And people should have a icon next to their ride or times to signify if they were riding at 100% or assisted
Zwift has a short video talking about the slider, but they aren't likely to go into the physiology. They aren't likely to label TD settings per rider because it might be unduly discriminatory. While its not a virtual gearbox, someone with a 1X mountain bike on their trainer may have to turn it down for big mountains. Someone on a wheel on trainer or entry level direct drive might have poor response or ride feel at 100% and will need to turn it down. For sanctioned races, they did end up setting the lower limit to 50% to control for those variables and create a level playing field. However, I have no business knowing what someone else's difficulty setting is, just like I have no business knowing their height or weight. At the end of the day, it's a game, and as long as sanctioned events have the appropriate controls and verification, that should be enough.
Fantastic explanation, I’m new to zwift and your explanation was one of the most comprehensive I’ve seen! Thanks for taking the time to put together such an informative video
Wow, I actually understood that. Thx. I always use 100%, and train for epic real-world climbs, but great to know I can dial knee & quad thrash down for recovery(‘ish) rides.
Great video and great explanation. As someone new to Zwift and new to cycling this will be extremely helpful as I would like to race in the platform at some point.
Love your view and your comments. Well done. Cyclist for many decades. It was the Indian not the Arrow before tech. In the 80s HRM s changed that. Now there too many arrows for me. Just ride, its fun and good for the soul
yeah I don't plan on having the difficulty up high. I plan to have my zwift setup designed around playing my MMO game and having zwift in the background; when I'm battling monsters, I don't want to have to change gears
Please read my other comment, you appear to misunderstand the functionality of the algorithm. Additionally, sanctioned races have begun to lock out the slider for the reasons I mentioned. Find me a real world gear ratio with a 65 front chain ring and an 80 tooth in the rear and maybe we can have this conversation, the reality is it's not accurate.
@@EverythingIsPhotogenic Do you mean that Trainer difficulty isn't like changing cassette and front chain ring in real life, because Trainer Difficulty allows for gear ratios that real life gearing will never be able to achieve ??
@@hrpzwift945 That's part of it, because the descents are affected by Trainer difficulty as well. The other part is the inertia at the flywheel. By moving the chain to a harder gear which can be accomplished at a lower difficulty setting, the flywheel moves faster giving you pedal assist, much like what you would get on a flat road. When you are in the easiest gear at full difficulty, the flywheel is going very slow, potentially stopping with seconds of removing the application of power. This is why I limited the discussion of gearing to giving you that largest cog in the back i.e. 25 to 28. The difference in inertia would be limited there and would be closely approximated to real world values.
I think it is a personal choice (not cheating) where you want your trainer difficulty to be at. Watts is watts. Like for me I chose to ride zwift at lower trainer difficulty because my riding style is spinning I cannot torque out 150watts at 70-65rpm. I feel that this discussion was like me showing in a group ride with compact gearing and 40t cassette.
This is a great video even though things may have changed over the last 4 years. I’m 6 months in but I don’t feel that I’m progressing fast enough. I have a Zwift trainer with the cog wheel that replaces the cassette and gives you access to many more gears. Perhaps a video on how to increase you FTP would be good.
Great run through of the science behind how this works and why you might change it to suit your needs. I spent 2 years on a basic wheel on trainer using speed/cadence sensor for zwift to derive wattage/kg and speed etc. I could pretty much stay in one gear and spin up/down throughout any workout. Having just got a smart direct drive trainer, it is a completely different game to get that wattage out. I run out of gears at both ends, spinning out at speed and running out of teeth on the hills. The trainer difficulty is part of that mix that i can use to help but like you say, getting the right gears on my bike is what i need to do really, so i am prepped for real life rides.
This is partially wrong. Gearing itself is the original trainer difficulty. You rightly point out that watts are rpms x force. So how does your gear ratio work into this? Say you are running a 48T chainring with a 24 tooth cog. Every one revolution of your cranks equates to two revolutions of your wheel. If you had to be on a 1/1 ratio you would have to double your cadence and halve your force to maintain the same watts / speed. In other words, changing gears from 48T/24 to, say, a 34T/34 changes the resistance your feet feel compared to what is actually happening at the wheel. Gear ratios are the mechanical way to modify resistance at the cranks and there’s no mathematical difference between this and trainer difficulty. For my part, I see trainer difficulty as a way of making Zwift more equitable. If I could afford one I’d have a nice expensive Zwift bike with a modern 1x system on my trainer. Instead I have an ancient 80s steel bike with a 53T big ring and a corncob 11-25 in the back. 53/25=2.2. Campy’s new 1x13 Ekar groupset comes with a 38T chainring and a 9-42 casette. 38/42=0.905, about 40% of the gearing of my 53/25. So if I run trainer difficulty at 40% it’s mathematically the same as if I swapped out my old school chainring and corncob for a modern 1x13 groupset. I suppose your point is I *could* shift down to the little ring (a 39T) and get more gears virtually than I could in real life, which is true (but not even a little useful in racing because the watts I can generate with such small gearing is minuscule). But I don’t. I exclusively use the big ring and use trainer difficulty so I don’t need to shift. But again, it is absolutely correct to call trainer difficulty virtual gearing because both it and gearing have exactly the same effect mathematically-they allow you to change the force/rpm equation at your legs for the same wattage at the wheels. Your point about people falling over with too low a gear in the real world is valid, but not really applicable to racing because you don’t race at 6 kph. (And if I were going to race/ride something with a 20% grade outdoors, I’d probably put a bigger cassette on my bike than an 11-28. My gravel bike has a 34/34 ratio as it’s easiest and I can spin up plenty of climbs as easily as I can in Zwift at 50% trainer difficulty with the ridiculous 53/25.)
I have to admit that the first time I saw one of your videos I thought your were a "bit" too geeky to keep on watching but I gave you a second chance and saw this video of how trainer difficulty really works on Zwift and was VERY impressed by how you explain things and how clear you can tackle such a complicated subject. One that I know, very few Zwift users really understand. Congrats! I just suscribed.
I think you have missed the thread of the video here. It has nothing to do with gearing and everything to do with gradient bias. There is no gearing in the world that is going to have you spinning up a 20% gradient and 90+ RPM and then be able to push 400 watts down the backside descent. Any adjustments under 85-90% are beyond any reasonable differential in gearing.
@@EverythingIsPhotogenic I see what you are saying but I can vary the power versus cadence by 5X on my gravel bike. All the way down to 18 gear inches. Sure I can't apply power when going faster than 25 or 30 mph downhill but I still get down the hill and can get up too. So if you have your smart trainer set up with "gearing" as if you were as fit as the professional riders you won't make it to the top of the climb. However if you use a sub-compact crank and a big cassette, you will.
I had to adjust the Trainer difficulty as I was experiencing a pulsing in the resistance provided by the trainer. This was only something that was noticeable on a long steep climb - every few revolutions it would ease off for a moment and then go back to being hard to pedal. I reached out the the trainer manufacturer who explained the Trainer Difficulty setting doesn't actually make the ride/workout harder or easier. What it actually does is change the amplitude of the resistance changes. I made an adjustment and the pulsing disappeared, but importantly, the big climbs like Alpe du Zwift are as hard as they were and require the same effort. I feel the setting could be renamed to make it clearer.
Thanks for the information. Just started on zwift with my old classic dumb trainer. So on Zpower one month in. Looking at the smart trainers and wondering how it works with thoes devices. This video helped answer many questions. Will want to simulate the real world the best I can so when out it is the same effort. Live in a area with many hills and big mountains of various grades with very long false flats, so no true flats or easy rides where I live. Have to climb a 10%+ hill I live on to home every ride.
Lower trainer difficulty does have inherent advantages. Shifting gears, you lose power. Less gear you shift the better. Flying down ADZ, flattening the road increases ability to generate watts. GL you pushing, 500 watts going down ADZ.
Great video! Have enjoyed learning from your commentary on various videos. I just got started on Zwift...so I have a super basic setup with a regular trainer with a speed sensor attached...does that speed sensor still enable Zwift to come up with a fairly accurate power calculation? Or is it a more estimated value based on my cadence/speed? And in that realm, will trainer difficulty have much affect? Thanks so much!
Hi Sarah , the way i look at Trainer Difficulty is its a rear cassette choice just like in real life , i wouldn't try to go up ALPDZ on a 25 , i prefer to go big gears lowish cadence , some people spin , spinning would kill me !! Froome / Contador regularly used 34's . Great video , I hope i haven't misunderstood your video.
The linked video at the end explains why it isn't comparable to gearing. It's fine to use it to meet your needs. But the comparison to gearing falls apart in a very significant way the further down the slider and more severe the grade. The point of the videos is to present what the slider actually does so that people can choose how to use it to meet their needs.
@@waynesmith4589 exactly. its like adding a 32 or 34 to your rear cassette with out actually changing your bike. 200w is 200w no matter how you get there.
I am grateful you took the time to tackle what is clearly a valuable topic. I am brand new to Watopia, and I did not even know about this setting. It has given me a lot to think about when it comes to setting my level. I’m just happy I can do it at all. I am sorry you apparently got a lot of grief from some trolls, but doing anything anymore invites people like that to try and stir the pot. Thank you. (+1 subscriber)
It seems from my experience in races that 50% trainer difficulty is higher than what most people have, and that becomes obvious on any route with short climbs. Having to change gears is really the problem of high trainer difficulty settings, not that you are running out of gears. People are doing from 0-30% settings and hardly change gears at all, easy to spot as they always accelerate as they come over the top of a hill, while people on more realistic setting will need to change into the big ring and lose momentum while shifting. On a long steady climb it is not true like you say that it is so much easier on lower setting, that is unless like you say, you'd get a too low cadence in your lowest gear. Low trainer setting is basicly like riding a road bike with something close to an automatic gearbox, or a road with very little need for gear change. Clearly that is an advantage, as every shift involves a short loss of power. As long as settings are free to change why would people not use what is best in a race aka 20-30% setting ?
That pretty much sums up my point here. People do race at 20-30 percent to essentially "flatten" the course in both directions reducing both the torque needed up hills and giving them gearing on descents one wouldn't otherwise have. As a game, using the settings to be most advantageous for you certainly makes sense, as a training tool however, lowering the difficulty is removing that element of accuracy and a very important skill set to train for the road. Most people don't understand this and oversimplifiy this setting as a virtual gear box, but as I mention here, that analogy loses teeth as the difficulty is set below -~80% and the grade kicks upward. It is more of a contentious subject than it needs to be as ego ends up attached to it, but my objective is to give people the information so they can use zwift to meet their personal training objectives with understanding and purpose. 🙂
@@EverythingIsPhotogenic it only reduces the torque on hills if they have greater velocity right? As you said, power is a component of torque and velocity (cadence). Two people doing 200W is still two people taking two components to come to the final result. The same thing that could happen if one person had a compact crankset amd another person had a standard.
@@RATM1971 that's not how the algorithm works however r. It flattens the whole grade, including the descents. Changing to a compact crankset certainly won't allow you to continue to apply power at -15% moreover, as I mentioned, the limitations are in the ratios. 50% difficulty isn't a realistic approximation of any gearing. Someone could make an edge case argument around putting a bike in the 53-11 but my discussion is around using the platform practically and if one is looking for realism. There is also a benefit of flywheel assist that I didn't go into too much detail on, turning the difficulty down keeps the flywheel moving faster that provides some additional momentum benefit that is not gleaned at an easier gear at a higher gradient. People really need to get away from the virtual gearing analogy, it's not accurate or helpful. I conceded that between 85-100% you could get a reasonable adjustment that won't have major implications on descents but again, not the purpose of the slider.
@@EverythingIsPhotogenic I don't misunderstand it, I just feel people get too hung up on the options. Yeah, true, less trainer difficulty makes downhills easier to apply power and I can see the advantage there. Uphill it *can* have you working different systems IF you don't have the gears to maintain the same cadence, but the uphill argument is the same if one person runs a 39-53 crank with an 11-23 cassette while another runs a 36-52 crank with an 11-34 cassette. In real life I wouldn't go ride Mount Evans with a 39-53 and 11-23 cassette, even if those are my "around town" gears, that would be suicide. If I have appropriate gearing, put me on Hilly Route with 0% trainer difficulty and 100% difficulty and tell me to keep my watts and heart rate about the same and my time will be the same. That said, I can see the argument for meaningful races to have set TD so that everyone has the same stimuli during the race. Allowing one person to spin 100rpm and 250W while another grinds 60rpm at 250W is not a like for like scenario. For the average C and D races I feel there are bigger fish to fry, namely excluding zPower racers (who actually are very inaccurate) and anti-sandbagging after all these years. To me it would be much more important to see races with verified sources of power as at least that somewhat levels the playing field.
@@RATM1971 I fail to see your point here. "There are bigger fish to fry" is not an argument. Everything I laid out here is factually accurate. The purpose of posting this video, on a voluntary consumption platform, is to provide the information to those who seek it. If it has no value for you, simply don't watch, it's that simple. It's not necessary to rationalize your own decisions. I don't care how you ride or what you think the slider is good for, it's your decision. My goal was to present the facts so those who want to make educated decisions about their settings are equipped to do so. Enjoy your day.
Now I get why while watching people on YT racing on Zwift that they NEVER change gears or maybe 1 or 2 times. On 50% difficulty, I must change gears about 20 times on a 30km race.
Fantastic explanation best I have seen. For me i don't see the point having a virtual world with ups and downs and not experience them as it looks. You lose all the emersion of being in that virtual world. I want a tough hill to feel like a tough hill so it's 100% for me in trainer difficulty
You often have 10-15% gradients in Zwift. Most people wouldn't ever ride this gradient in RL. I think having it set at 50% factors in that most routes and gradients on Zwift are on roids to make the landscape and asthetic more dramatic and interesting. That said...it's amazing this isn't mentioned in their in game tutorial right.
I'm kind of confused by how resistance is so low with my setup, though the problem might be a lack of any frame of reference. Going over 100 watts is really difficult for me simple because of the speed at which I must move my pedals. Going to 125 or higher, it gets to the point where my freewheeler is frequently clunking as I'm not able to keep up the pace that the trainer is spinning at. On the other hand, a wattage calculator I found says that with outdoor cycling, I should theoretically be reaching 100 watts at around 20 km/h -- which is not terribly fast! EDIT: Oddly, it's only when I was in a training ride... If I just go into "Just Watch" and start pedalling, everything feels much more reasonable...
I don't think you should make the rider responsible for having an unfair advantage by decreasing the difficulty. I'm assuming that most racers have it set to something low. Zwift could add an option where race organizers can set a minimum difficulty for one race since there will always be people who use that slider (me too lol).
They've done that t for sanctioned races now. It's at 50%. It's not locked for regular races yet. Probably won't be, they don't want to have out beginners.
Would it make sense for Zwift to modify the grade of a climb based upon the user setting of trainer difficulty, in other words, a 10% hill at 100% trainer difficulty, could be adjusted to a 5% Hill and 50% trainer difficulty? Why does swift give full credit to the amplitude of the climb at the lower setting; doesn’t seem fair or accurate?
For those who still are not understanding why trainer difficulty is not "like gearing" here is a scenario with some additional specificity that may clarify things:
Let's say for instance you it a 15% grade, challenging for most mere mortals, at 100% difficulty you will face that with all the resistance commensurate with that gradient. It will be very difficult and you will have to use likely a very easy gear to apply power to the pedals. Let's say a 50-32 gear ratio for the sake of argument. There is a minimum amount of power that is going to be required to overcome that resistance and if you are incapable of producing that power, you will not be able to move the pedals. Now, let's say you reduced the difficulty to 50%, now you've halved the resistance and can very likely move the pedals because your power is sufficient to do so. Zwift will allow your avatar to move up the road based on that calculation, however, in reality, you likely would be stopped on the side of the road in the real world because your power/torque capacity does not meet the inertial requirements to move the bicycle. The slider is making the hill easier while applying your actual output of power to calculate virtual speed. Moreover, the trainer difficulty slider affects the descents as well allowing one to continue to apply power in areas that they very likely would spin out. This again is calculated and will produce a speed benefit that would not be possible in the real world or at 100% trainer difficulty. The slider isn't gearing, it's realism effect.
All I’m hearing is that for the last year and a half I have been living a lie and my 47 minutes up alpe du zwift with 325w average on the segment ain’t worth shit. Guess I have to start all over again on max difficulty.
@@mrnobody9821 @Mr Nobody how do you come to that conclusion from a comment that explains why its not the same as gearing? If you"re capable of the output then you"re capable. It might feel a bit more hellish at a lower cadence with low inertia. This example was outlining that power that might be insufficient to clear the grade in the real world would still move an avatar in Zwift, someone clearing the alpe under 50 minutes doesn't fall into that bucket.
@@EverythingIsPhotogenic Zwift is 100% about perception. (PERCEIVED effort @ 100% difficulty in the virtual world is intended to mimic ACTUAL effort in the real world.) With regard to climbing, reducing trainer difficulty is EXACTLY the same perception as adding gearing. Given gearing that would allow Mr. Nobody to maintain the same cadence /power that he produces in Zwift @ 50% difficulty, he would climb L'Alpe de' Huez at the same speed in the actual world. (Wind and rolling resistance not withstanding.) That holds true whether you're doing it in 50 minutes or 100.
@@jeffmorgan5152 that's inaccurate. If you want to understand why, you can watch my video on why it's not virtual gearing. And it's not perception. I invite you to read the discussion in the pinned comment as well
@@EverythingIsPhotogenic No, it just suggests that gears larger than 50 / 32 would be necessary to accomplish the task. You can accomplish the same thing by EITHER reducing difficulty or increasing gearing, hence the reference to PERCEPTION. (I'm not challenging your math, but decreasing difficulty or swapping standard for compact chainrings accomplishes the same thing from a rider experience perspective.) For example by way of personal practical application: I normally ride at 100%. When focused on Z2 training in Zwift, I can either restrict riding to less challenging routes, swap out gearing to allow a reasonble cadence when climbing, or simply back resistance down to allow the same thing. VenTop for example goes from off the menu to a favorite sustained effort.
Wow, what an excellent video! As a new Zwift rider, I’m surprised at how untransparent the details of Zwift are. You are the best teacher, cheers.
You have a gift. It can be a rare thing indeed that a very smart person can explain a complex topic in relatively simple terms that those with lesser levels of understanding can grasp and apply. This video is a great example of such a rarity. In college, my metaphysics professor Van Hook said something that stayed with me to age 65: “if you cannot explain it, you don’t really know it.” Well done professor!
Not everyone is a 25-year-old racer. I'm a 67 year-old, 190 lbs, Zwift user who has been cycling for 60 years. There are long climbs on Zwift that I want to ride but my knees can't take the long-term stress. So I adjust the difficulty. When riding on flatter routes, I go back to 100%. For me, adjusting the difficulty has made Zwift a better training tool
Yesthat is very true and good for training. Just make sure to never cheat in races however. Keep zwifting!
Everyone needs to relax...in Zwift...we race against ourselves....we are not going to the Tour....just ride
@@joneinarmattiasvisser6113 very few people race on 100% most do not
Excellent. As clear minded a description of both the science, bike function, gaming situations and application as you’ll ever find. Well done.
My trainer bike is a 9-speed. And because of that the gaps with the standard cassette had big gaps. I replaced it with a 14-25T. I would NEVER put my old knees through that gearing outdoors. So, I have to set Zwift difficulty to save my knees. No crazy low cadence stress on my knees. Good that the video confirms my instincts.
Just 3+ months into Zwift myself and found this video absolutely brilliant. Thank you so much!!
Excellent explanation; it reinforces what I kinda already understood. In other words, your video gives me confidence that I understand the purpose and application of Trainer Difficulty. You covered my use case... injury. I have a worn out hip that will eventually need to be replaced. Of course I am in no rush to go thru this procedure. The injury is from years of running; I can’t run anymore but I can cycle. I live in flatland and riding outside is... flat. On Zwift I want to experience the various routes/terrains and I could not do many of the climbing routes without the Trainer Difficulty reduced. If I did use 100% I’d have to ride once and recover for a week or maybe even longer. Trainer Difficulty reduced keeps me on the bike and out of the hospital (for now). Thank you for your time; your videos are always spot on.
Great explanation. But I found out that if you get your cadence in the same region as you would normally do, you still have to change gears in 50% as much as in 100 %, but you use bigger gears. The wattage I can produce are the same in both settings with the same cadence but the trainer is just spinnig faster since the gear ratio is different. The problem you describe gets real in the zone where you are grinding in the smallest gear and can’t spin up to those higher revs. This is were it gets easier on your legs when you move the difficulty lower since you are than able to use higher cadence.
One of the best explanations on TH-cam regarding cycling / Zwift / training science. Enjoying it greatly!
Perfect. Now I know how I want to adjust this setting depending on the ride/day. Thx 👍🏻
Really enjoyed your video talking about this. I've always wanted my difficulty set to 100% but you make some good points about gearing and injury....I went through a month of knee strain and can totally see a use there. Thanks again!
Great video! Well explained. I'm just not sure why there is so much debate. Anyone who has ridden a bike up a long, steep hill knows that you lose your legs faster grinding at 50 rpm than spinning at 85 rpm. The one issue I have with the settings is I feel MAX difficulty makes it feel harder than real world. I have no problem getting up 10 - 15% grades in the real world with the gearing I have on my bike. I can barely push the pedals over on the same type of grade in my lowest gear on Zwift. I'm not going to buy a different cassette when it works just fine for real-world riding; which is 80% of my cycling.
I found the same thing on an old Elite RealAxiom CT trainer (a USB model even older than the bluetooth RealAxiom B+ model). With trainer difficulty on max, I learned over a few weeks to adjust my weight to about 55% to match VAM (vertical ascent in meters/hr) as reported in Strava for Zwift and real world.
Changed to a Wahoo Kickr 2017, kept difficulty on max, put my weight back to my real weight, went for one ride, and the Zwift and real-world VAMs were a match.
same here. got it on 50-60% and 100% seems way harder than real life imo.
Im glad somebody actually picked up, that sometimes zwift is just to ride and have fun. Sometiems you might want to get on small races, even if your knees can go very fast, but cant stand a lot of pressure. This makes it actually fun, and allows you to maintain therapy or just "body maintenance" .
Thanks! Very helpful. Been road cycling for about 50 yrs. On Zwift for about a month . Lucid.
Good explanation. I was really impressed with difficulty at 100%, it really felt like an actual 12% gradient. Anyone who has ridden steep gradients in the real world will understand the difference. I use 100% for training and 30% for racing lol.
I incidentally learned of this setting just a week ago watching another video. I live in a hilly area and climb regularly (no choice, really) and found this setting definitely explains why it felt easier in-game. This video does a better job explaining it than anything else I found online - certainly better than on Zwift.
That was fantastic! I finally understand after many years on Zwift and. many confusing explanations.
I've been bicycling for about 5 years, but have only started gradually pushing myself for the past 3 years.
In the summer, I ride about 250 to 300 miles a month.
I bought an indoor trainer because I live in Michigan and it's just to cold and quite frankly, unsafe to road ride in the winter. Seems like every year I've gotta restart from square one to get back in shape.
As a newbie who just purchased an indoor trainer (Wahoo Kickr),
I'm still learning Zwift and didn't even know there was a difficulty setting until after using Zwift for about 3 weeks.
My first rides on the flat route were crazy difficult by comparison to my normal rides. I ride on some pretty hilly roads and at 100%, it was definitely more difficult than riding outside. My setting was at 100% by default. I didn't even know it. I had no idea how the setting worked, so I turned it down to 50%. To me, 50% actually felt more true to my usual ride experience. 100% was just over the top.
My goal is to gradually push it up each month. Last week I moved it up a notch to what I'd guess is 60%? There's no associated number given so I don't know for sure. But my goal is to just keep progressing back to a higher difficulty each month.
Thanks for taking the time to break this down for us this clearly.
100% trainer difficulty for me, though. GFNY coming up in a few months and I need as much help in my uphill training... no real hills in Chicago 😉
Hi Sarah! Your viedos about Zwift are just about everything you need to know about Zwift. I completely understand how things work in Zwift when watching your videos. Keep up the good work!
/Pär from Sweden
Very informative. Very new to Zwift but been cycling for over 60 years. I know realise why hill climbing seemed a lot easier than in real life and how to make it more realistic. With age I have found my hill climbing much more difficult if only I could adjust the gradient in real life!!
If you're lowering the training difficulty (reducing the resistence) and flattening the climbs you are essentially just going for a ride on the flat, it's pretty simple .. the watts are measured by the pressure on the pedals from your effort but if there's no resistance you're not simulating riding a climb you're riding a timetrial, you might aswell ride fuego flats ignore the speed and just ride on rpm and power, it'll be the same effort and tension on your muscle groups... Great vid BTW 👌
You would be surprised at how many people do not understand the distinction between gearing and the resistance bias. I think many folks eventually come around with some experience and experimentation, but this tends to be a pretty controversial topic... thanks for checking this one out!
Wow what an excellent thorough video and how all this really works. I couldn't wrap my head around it but you have explained it perfectly thanks so much!!
Thanks. Good explanation thqat this is really another tool to manage the Zwift experience. I'll definitely be testing and playing with it.
New to your channel and just subscribed; this video is insanely brilliant, loved it, thank you 🙏
This is excellent so well explained and all is NOW clear.. I am new to Zwift and this is super helpful… have a great 2022…
This is the best explanation of trainer difficulty I’ve seen 👏
Very informative. I'm recovering from an injury and can only spin with little resistance. Playing with the difficulty is just what i need to keep me on Swift. Thanks!
Same here. I need 50% at this point to get to the point where the fitness allows to go higher.
Only just starting Zwifting last week. I did the KOM with the radio tower climb on the Tour of Watopia a few days ago not knowing what I was getting into. Even at 50% difficulty I was toast. Felt like such a massive achievement just getting to the top. Now I know it should've been twice as hard! People are machines
I'm a newer sub and wanna say thx for you knowledge and experience with riding and zwift. I just setup my Saris M2 trainer yesterday and am binge watching alot if your videos to really get a grasp of Zwift. I've done a ride to get the feel of it and want to know where to start ie: settings, FTP test, just getting to know how best to approach the platform. What would you do etc. Sometimes I get overloaded with to much info and kinda want a general direction from square one. Hope I'm not asking too much, thanks alot, in the meantime I'm just f'ing around with getting to know the landscape🙂
Hey thanks Sara for making this video. This is the best explanation I've found so far. Cheers..
Hey.
Great info about trainer difficulty. Thanks.
Very clear and precize explenation. One remark: power is equal to TORQUE x ANGULAR_VELOCITY (P = F x R x ω), here ω is angular belocity of the crank.
R is of course constant, you can not change it. F is the average force you press on one pedal times 2. Now, everything is said and all conclusions are totaly clear. The only extra information you need to have is that the level of difficulty set in game corresponds to the slope inclination expressed in % ( which is equel to sin(α ), where α is an angle of the inclination).
Thank you for this video. I'm fairly new to turbo trainers and Zwift and i have only just discovered your channel on TH-cam. I loved the content. It back up my understanding - I have my TD set at 90% as my indoor trg bike has a 34/29 easy gear whereas my IRL bike has a 34/32 gear so hopefully the adjustment will better reflect my IRL experience (though without the weather or the cafes).
This! I just had to switch my indoor trainer cassette from 11-32 to 11-28 so my lowest possible gear is now 34/28 and IRL the lowest gear option I have is 35/33. I moved the TD slider to 90% and hopefully that should help me maintain a similar cadence as I do IRL
Very good explanations in this video. Going the same speed no matter the Trainer Difficulty holds true IF you put out the same watts (this has been proven). But in reality this may not be how it goes for you. On a steep/long hill you may not have the gearing or leg strength to maintain the cadence to achieve those watts (this was touched on in the video). So your watts will drop and you will go slower. But if you lower the difficulty and can maintain the same watts you would go faster.
I like teh idea, "zwift is to have fun, to get you rolling". It also gives you teh option to be a "profesional trainer". It ahs a lot of "elasticity" to fit the users needs. Some of us want to (and are able) to go up to 1000 watts, some of us canot, but still want to "play". It is a program geared to the users needs. LOVE IT !!!!
This channel is purely stellar. Keep it up and thanks for sharing your knowledge!
Training difficulty is the Zwift version of "flat earth."
In a nutshell, what this affects is the torque.
Thanks for this. New to zwift and was trying to wrap my head around this very thing in the software that I didn't know existed. I knew I had a question, but didn't know what it was. So now I know the question and the answer. 😉
Trainer difficulty allows you to stay in your comfortable cadence/torque window. This allows one to be more efficient on very steep climbs with typical road bike gearing. In real world you cannot trade of gradient for distance. Difficulty is like zig zagging up a hill.
Excellent explanation for this newbie!
Very informative - thank you for the detailed explanation!
As a 110 kg newbie zwift cyclist I will definitely be lowering that setting just to have a chance to get up alpes du zwift, as I loose weight I will turn it up
This was a really good explanation ... awesome vid. I know when I come to this channel to get some info I really don't need to look any further. The explanations is done in a easy to understand and comprehensive way
Great video well explained
Thank you for this video. After watching this I decided to bump up this setting tonight. I was able to keep up the same pace with a higher wattage output. I'm going to try to keep bumping up this setting.
Brilliant explanation, Sarah. Thank you.
Best Explanation I’ve heard...thanks!!!
👍 I set my preferred 'Trainer difficulty' according to how I can do the Radio Tower climb. Then youll be able to climb
everything within your gearing in Zwift.
I know that this video is three years old and things have probably changed. But thanks for the background info!
Great video! I've been Zwifting for 2 weeks now and I only have a 2x9 speed bike. My bike has a 25-13 cassette in the back which is HARD when it comes to climbing. I have it set at 50% until I can upgrade to a 2x11. Thanks!
This was great. Thanks very much!
Agree'd, watts aren't all created equal. 300 watts at 60 rpm 300 watts at 95 rpm. It's sustainability of watts, and those who argue otherwise don't understand the difference between slow and fast twitch muscle fibers or understand the difference between cardiovascular and muscular fatigue.
Hmm. Watts are created equal. A watt is a measurement of work produced. You are confusing Torque with power. Torque is what you feel when cadence drops. That is you need to produce more torque to produce the same watts at a lower cadence.
@@ttpgsc Watts are a measurement of Power, hence why power meters are measured in Watts. Power is created by Torque. Power can be created with high torque, or low torque, defined by cadence. Therefore, not all watts are CREATED equal.
@@Auntybob the bottom line is that it’s your body that has to come up with the power. Whether someone’s body is better at grinding or spinning is besides the point. Either person can come up with the 300 watts. Watts are watts regardless of where it gets produced. No two people will create those watts in the same way so not sure why you point out the source of creation as being significant.
Basically Zwift should have a tooltip explaining this. And people should have a icon next to their ride or times to signify if they were riding at 100% or assisted
Zwift has a short video talking about the slider, but they aren't likely to go into the physiology. They aren't likely to label TD settings per rider because it might be unduly discriminatory. While its not a virtual gearbox, someone with a 1X mountain bike on their trainer may have to turn it down for big mountains. Someone on a wheel on trainer or entry level direct drive might have poor response or ride feel at 100% and will need to turn it down. For sanctioned races, they did end up setting the lower limit to 50% to control for those variables and create a level playing field. However, I have no business knowing what someone else's difficulty setting is, just like I have no business knowing their height or weight. At the end of the day, it's a game, and as long as sanctioned events have the appropriate controls and verification, that should be enough.
Another excellent video. Your knowledge is extensive. Thanks for sharing some of it.
Fantastic explanation, I’m new to zwift and your explanation was one of the most comprehensive I’ve seen! Thanks for taking the time to put together such an informative video
Wow, I actually understood that. Thx. I always use 100%, and train for epic real-world climbs, but great to know I can dial knee & quad thrash down for recovery(‘ish) rides.
Great video and great explanation. As someone new to Zwift and new to cycling this will be extremely helpful as I would like to race in the platform at some point.
Thank you. I'm new to zwift and this was a great explanation. Rational and poised.
Excellent clear and informative explanation. Thank you.
Love the way you explain things!
Clear and concise. Thank you.
Love your view and your comments. Well done. Cyclist for many decades. It was the Indian not the Arrow before tech. In the 80s HRM s changed that. Now there too many arrows for me. Just ride, its fun and good for the soul
yeah I don't plan on having the difficulty up high. I plan to have my zwift setup designed around playing my MMO game and having zwift in the background; when I'm battling monsters, I don't want to have to change gears
Excellent explanation. Really good and well put.
Your argument that it provides an unfair advantage would be the exact same unfair advantage if two people had different cassettes.
Please read my other comment, you appear to misunderstand the functionality of the algorithm. Additionally, sanctioned races have begun to lock out the slider for the reasons I mentioned. Find me a real world gear ratio with a 65 front chain ring and an 80 tooth in the rear and maybe we can have this conversation, the reality is it's not accurate.
@@EverythingIsPhotogenic Do you mean that Trainer difficulty isn't like changing cassette and front chain ring in real life, because Trainer Difficulty allows for gear ratios that real life gearing will never be able to achieve ??
@@hrpzwift945 That's part of it, because the descents are affected by Trainer difficulty as well. The other part is the inertia at the flywheel. By moving the chain to a harder gear which can be accomplished at a lower difficulty setting, the flywheel moves faster giving you pedal assist, much like what you would get on a flat road. When you are in the easiest gear at full difficulty, the flywheel is going very slow, potentially stopping with seconds of removing the application of power. This is why I limited the discussion of gearing to giving you that largest cog in the back i.e. 25 to 28. The difference in inertia would be limited there and would be closely approximated to real world values.
New sub and I love your channel!!!❤
I think it is a personal choice (not cheating) where you want your trainer difficulty to be at. Watts is watts. Like for me I chose to ride zwift at lower trainer difficulty because my riding style is spinning I cannot torque out 150watts at 70-65rpm. I feel that this discussion was like me showing in a group ride with compact gearing and 40t cassette.
You do you
@@EverythingIsPhotogenic i love your channel’s content though. keep it up!
This is a great video even though things may have changed over the last 4 years. I’m 6 months in but I don’t feel that I’m progressing fast enough. I have a Zwift trainer with the cog wheel that replaces the cassette and gives you access to many more gears. Perhaps a video on how to increase you FTP would be good.
Great run through of the science behind how this works and why you might change it to suit your needs. I spent 2 years on a basic wheel on trainer using speed/cadence sensor for zwift to derive wattage/kg and speed etc. I could pretty much stay in one gear and spin up/down throughout any workout. Having just got a smart direct drive trainer, it is a completely different game to get that wattage out. I run out of gears at both ends, spinning out at speed and running out of teeth on the hills. The trainer difficulty is part of that mix that i can use to help but like you say, getting the right gears on my bike is what i need to do really, so i am prepped for real life rides.
Right gears will help. The investment is surely worth once you get outdoors! 🙂
You're a friggin guru. Subbed immediately after watching!
Thanks for sharing, explained really well. Love your updates 😉
Rolling resistance: in 2021 at any rate, I'm pretty sure gravel, boardwalks, and rough tarmac have added resistance applied.
Awesome content, thank you so much
Thanks for this video.really clear compared to dozens similar videos I watched even from ZWIFT Gurus like Shane Miller
It's so frustrating that 99% of Zwifter don't get the physics behind this!
I'm still hoping for a miracle..
This is partially wrong. Gearing itself is the original trainer difficulty. You rightly point out that watts are rpms x force. So how does your gear ratio work into this? Say you are running a 48T chainring with a 24 tooth cog. Every one revolution of your cranks equates to two revolutions of your wheel. If you had to be on a 1/1 ratio you would have to double your cadence and halve your force to maintain the same watts / speed. In other words, changing gears from 48T/24 to, say, a 34T/34 changes the resistance your feet feel compared to what is actually happening at the wheel. Gear ratios are the mechanical way to modify resistance at the cranks and there’s no mathematical difference between this and trainer difficulty.
For my part, I see trainer difficulty as a way of making Zwift more equitable. If I could afford one I’d have a nice expensive Zwift bike with a modern 1x system on my trainer. Instead I have an ancient 80s steel bike with a 53T big ring and a corncob 11-25 in the back. 53/25=2.2. Campy’s new 1x13 Ekar groupset comes with a 38T chainring and a 9-42 casette. 38/42=0.905, about 40% of the gearing of my 53/25. So if I run trainer difficulty at 40% it’s mathematically the same as if I swapped out my old school chainring and corncob for a modern 1x13 groupset. I suppose your point is I *could* shift down to the little ring (a 39T) and get more gears virtually than I could in real life, which is true (but not even a little useful in racing because the watts I can generate with such small gearing is minuscule). But I don’t. I exclusively use the big ring and use trainer difficulty so I don’t need to shift.
But again, it is absolutely correct to call trainer difficulty virtual gearing because both it and gearing have exactly the same effect mathematically-they allow you to change the force/rpm equation at your legs for the same wattage at the wheels. Your point about people falling over with too low a gear in the real world is valid, but not really applicable to racing because you don’t race at 6 kph. (And if I were going to race/ride something with a 20% grade outdoors, I’d probably put a bigger cassette on my bike than an 11-28. My gravel bike has a 34/34 ratio as it’s easiest and I can spin up plenty of climbs as easily as I can in Zwift at 50% trainer difficulty with the ridiculous 53/25.)
Excellent explanation about this subject
I have to admit that the first time I saw one of your videos I thought your were a "bit" too geeky to keep on watching but I gave you a second chance and saw this video of how trainer difficulty really works on Zwift and was VERY impressed by how you explain things and how clear you can tackle such a complicated subject. One that I know, very few Zwift users really understand. Congrats! I just suscribed.
never new about this setting - thanks - very well done -
I do not yet have a smart trainer but in theory you could get the same "benefit" as lower "trainer difficulty" by getting a different cassette.
I think you have missed the thread of the video here. It has nothing to do with gearing and everything to do with gradient bias. There is no gearing in the world that is going to have you spinning up a 20% gradient and 90+ RPM and then be able to push 400 watts down the backside descent. Any adjustments under 85-90% are beyond any reasonable differential in gearing.
@@EverythingIsPhotogenic I see what you are saying but I can vary the power versus cadence by 5X on my gravel bike. All the way down to 18 gear inches. Sure I can't apply power when going faster than 25 or 30 mph downhill but I still get down the hill and can get up too. So if you have your smart trainer set up with "gearing" as if you were as fit as the professional riders you won't make it to the top of the climb. However if you use a sub-compact crank and a big cassette, you will.
I had to adjust the Trainer difficulty as I was experiencing a pulsing in the resistance provided by the trainer. This was only something that was noticeable on a long steep climb - every few revolutions it would ease off for a moment and then go back to being hard to pedal. I reached out the the trainer manufacturer who explained the Trainer Difficulty setting doesn't actually make the ride/workout harder or easier. What it actually does is change the amplitude of the resistance changes. I made an adjustment and the pulsing disappeared, but importantly, the big climbs like Alpe du Zwift are as hard as they were and require the same effort.
I feel the setting could be renamed to make it clearer.
Thanks for the information. Just started on zwift with my old classic dumb trainer. So on Zpower one month in. Looking at the smart trainers and wondering how it works with thoes devices. This video helped answer many questions. Will want to simulate the real world the best I can so when out it is the same effort. Live in a area with many hills and big mountains of various grades with very long false flats, so no true flats or easy rides where I live. Have to climb a 10%+ hill I live on to home every ride.
Lower trainer difficulty does have inherent advantages.
Shifting gears, you lose power. Less gear you shift the better.
Flying down ADZ, flattening the road increases ability to generate watts. GL you pushing, 500 watts going down ADZ.
Great video! Have enjoyed learning from your commentary on various videos. I just got started on Zwift...so I have a super basic setup with a regular trainer with a speed sensor attached...does that speed sensor still enable Zwift to come up with a fairly accurate power calculation? Or is it a more estimated value based on my cadence/speed? And in that realm, will trainer difficulty have much affect? Thanks so much!
Hi Sarah , the way i look at Trainer Difficulty is its a rear cassette choice just like in real life , i wouldn't try to go up ALPDZ on a 25 , i prefer to go big gears lowish cadence , some people spin , spinning would kill me !! Froome / Contador regularly used 34's . Great video , I hope i haven't misunderstood your video.
The linked video at the end explains why it isn't comparable to gearing. It's fine to use it to meet your needs. But the comparison to gearing falls apart in a very significant way the further down the slider and more severe the grade. The point of the videos is to present what the slider actually does so that people can choose how to use it to meet their needs.
@@EverythingIsPhotogenic Yeap , mainly to save money on a bigger cassette .
@@waynesmith4589 exactly. its like adding a 32 or 34 to your rear cassette with out actually changing your bike. 200w is 200w no matter how you get there.
I am grateful you took the time to tackle what is clearly a valuable topic. I am brand new to Watopia, and I did not even know about this setting. It has given me a lot to think about when it comes to setting my level. I’m just happy I can do it at all. I am sorry you apparently got a lot of grief from some trolls, but doing anything anymore invites people like that to try and stir the pot.
Thank you. (+1 subscriber)
Think of it as raising or lowering total tooth count no matter how many front or rear rings you have. They should have named it "Gear Scaling".
It's not virtual gearing. I cover that in detail in the linked video. The physics is not consistent. It is gradient bias.
Thank you, a very good info!
Great video. Really explains it very well.
So helpful. Thank you
It seems from my experience in races that 50% trainer difficulty is higher than what most people have, and that becomes obvious on any route with short climbs. Having to change gears is really the problem of high trainer difficulty settings, not that you are running out of gears. People are doing from 0-30% settings and hardly change gears at all, easy to spot as they always accelerate as they come over the top of a hill, while people on more realistic setting will need to change into the big ring and lose momentum while shifting. On a long steady climb it is not true like you say that it is so much easier on lower setting, that is unless like you say, you'd get a too low cadence in your lowest gear. Low trainer setting is basicly like riding a road bike with something close to an automatic gearbox, or a road with very little need for gear change. Clearly that is an advantage, as every shift involves a short loss of power. As long as settings are free to change why would people not use what is best in a race aka 20-30% setting ?
That pretty much sums up my point here. People do race at 20-30 percent to essentially "flatten" the course in both directions reducing both the torque needed up hills and giving them gearing on descents one wouldn't otherwise have. As a game, using the settings to be most advantageous for you certainly makes sense, as a training tool however, lowering the difficulty is removing that element of accuracy and a very important skill set to train for the road. Most people don't understand this and oversimplifiy this setting as a virtual gear box, but as I mention here, that analogy loses teeth as the difficulty is set below -~80% and the grade kicks upward. It is more of a contentious subject than it needs to be as ego ends up attached to it, but my objective is to give people the information so they can use zwift to meet their personal training objectives with understanding and purpose. 🙂
@@EverythingIsPhotogenic it only reduces the torque on hills if they have greater velocity right? As you said, power is a component of torque and velocity (cadence). Two people doing 200W is still two people taking two components to come to the final result. The same thing that could happen if one person had a compact crankset amd another person had a standard.
@@RATM1971 that's not how the algorithm works however r. It flattens the whole grade, including the descents. Changing to a compact crankset certainly won't allow you to continue to apply power at -15% moreover, as I mentioned, the limitations are in the ratios. 50% difficulty isn't a realistic approximation of any gearing. Someone could make an edge case argument around putting a bike in the 53-11 but my discussion is around using the platform practically and if one is looking for realism. There is also a benefit of flywheel assist that I didn't go into too much detail on, turning the difficulty down keeps the flywheel moving faster that provides some additional momentum benefit that is not gleaned at an easier gear at a higher gradient. People really need to get away from the virtual gearing analogy, it's not accurate or helpful. I conceded that between 85-100% you could get a reasonable adjustment that won't have major implications on descents but again, not the purpose of the slider.
@@EverythingIsPhotogenic I don't misunderstand it, I just feel people get too hung up on the options. Yeah, true, less trainer difficulty makes downhills easier to apply power and I can see the advantage there. Uphill it *can* have you working different systems IF you don't have the gears to maintain the same cadence, but the uphill argument is the same if one person runs a 39-53 crank with an 11-23 cassette while another runs a 36-52 crank with an 11-34 cassette. In real life I wouldn't go ride Mount Evans with a 39-53 and 11-23 cassette, even if those are my "around town" gears, that would be suicide. If I have appropriate gearing, put me on Hilly Route with 0% trainer difficulty and 100% difficulty and tell me to keep my watts and heart rate about the same and my time will be the same. That said, I can see the argument for meaningful races to have set TD so that everyone has the same stimuli during the race. Allowing one person to spin 100rpm and 250W while another grinds 60rpm at 250W is not a like for like scenario. For the average C and D races I feel there are bigger fish to fry, namely excluding zPower racers (who actually are very inaccurate) and anti-sandbagging after all these years. To me it would be much more important to see races with verified sources of power as at least that somewhat levels the playing field.
@@RATM1971 I fail to see your point here. "There are bigger fish to fry" is not an argument. Everything I laid out here is factually accurate. The purpose of posting this video, on a voluntary consumption platform, is to provide the information to those who seek it. If it has no value for you, simply don't watch, it's that simple. It's not necessary to rationalize your own decisions. I don't care how you ride or what you think the slider is good for, it's your decision. My goal was to present the facts so those who want to make educated decisions about their settings are equipped to do so. Enjoy your day.
Now I get why while watching people on YT racing on Zwift that they NEVER change gears or maybe 1 or 2 times. On 50% difficulty, I must change gears about 20 times on a 30km race.
Fantastic explanation best I have seen. For me i don't see the point having a virtual world with ups and downs and not experience them as it looks. You lose all the emersion of being in that virtual world. I want a tough hill to feel like a tough hill so it's 100% for me in trainer difficulty
thanks for the explanation
You often have 10-15% gradients in Zwift. Most people wouldn't ever ride this gradient in RL. I think having it set at 50% factors in that most routes and gradients on Zwift are on roids to make the landscape and asthetic more dramatic and interesting.
That said...it's amazing this isn't mentioned in their in game tutorial right.
Thanks as I’m a newbie very much appreciated cheersTony Tassie
I'm kind of confused by how resistance is so low with my setup, though the problem might be a lack of any frame of reference. Going over 100 watts is really difficult for me simple because of the speed at which I must move my pedals. Going to 125 or higher, it gets to the point where my freewheeler is frequently clunking as I'm not able to keep up the pace that the trainer is spinning at. On the other hand, a wattage calculator I found says that with outdoor cycling, I should theoretically be reaching 100 watts at around 20 km/h -- which is not terribly fast!
EDIT: Oddly, it's only when I was in a training ride... If I just go into "Just Watch" and start pedalling, everything feels much more reasonable...
I don't think you should make the rider responsible for having an unfair advantage by decreasing the difficulty. I'm assuming that most racers have it set to something low. Zwift could add an option where race organizers can set a minimum difficulty for one race since there will always be people who use that slider (me too lol).
They've done that t for sanctioned races now. It's at 50%. It's not locked for regular races yet. Probably won't be, they don't want to have out beginners.
@@EverythingIsPhotogenic Oh, that's good to know!
Are all the gear sets and chain rings exactly the same on these sanctioned races?
@@owenjohnson5030 No they can select their own gearing knowing everyone will be faced with the identical terrain.
Would it make sense for Zwift to modify the grade of a climb based upon the user setting of trainer difficulty, in other words, a 10% hill at 100% trainer difficulty, could be adjusted to a 5% Hill and 50% trainer difficulty? Why does swift give full credit to the amplitude of the climb at the lower setting; doesn’t seem fair or accurate?