Lightweight blade designs - improving jumps?

[Timskate]

Hi,

I am a PhD student and I am curious about lightweight blade designs.

From what I’ve read on resellers' websites and manufacturers' sites, lightweight blades are said to increase jump height, jump length, air time, and, in the case of the Gold Seal Revolution blades, even cushion landings. But is this really true? No one seems to provide data to back up these claims.

I came across a scientific paper published in 2022 (https://www.tandfonline.com/doi/full/10.1080/14763141.2022.2063757) where researchers tested different blades, analyzing data from approximately 600 take-offs and landings. They found no differences in jump height between traditional and lightweight blades, and the Revolution blades did not cushion landings any better than regular blades. This was the only real-world data I could find.

Measuring and comparing jump heights across different blades doesn’t seem overly complicated, in my opinion. Perhaps the weight difference is too small to produce a measurable impact, and manufacturers are naturally inclined to make claims that appeal to buyers.

When I watch competitions, I notice that some top skaters use lightweight blades while others stick to regular ones. I’m sure athletes and coaches seek out equipment that they believe enhances performance, such as the increased jump height promised by the Gold Seal Revolution blades, as any competitive edge is valuable.

I understand that successful jumps rely on many factors beyond height. However, if blades are advertised as increasing jump height, they should deliver on that promise—especially since that would be my primary reason for considering them.

So, what are the actual benefits of the Revolution design compared to regular Gold Seal blades, particularly given the higher cost?

I’d really appreciate your perspective on this!

Thanks, Tim

 

[Ic3Rabbit]

No, nothing significant. Many of the top elite competitive skaters are "given" the blades by the company and that's what they use.
There are many a thread in the lutz corner here where myself and others "in the know", say no to them, especially for the thousands who come here to ask about what blade they need at lower levels. You can see under my photo where I've been in the sport level wise and I still use traditional style blades. I've tested most or all blades and boots over my time and so on and there's no real advantage to these lite or rev blades, and if you are going to use them, you don't need them until you are a top level skater.

 

[Query]

I am not an expert, or any kind of elite athlete. But lots of us have wondered about this.

Somone recently published a study showing that blade weight had no statistically significant impact on jump height. But the same study concluded that blade chassis flexibility (specifically, the carbon fiber MK & JR Revolution blades - though note that many skate techs don't have the equipment or experience to sharpen them well) reduced impact force, so might be less likely to create injury.

I wouldn't be surprised if those tests were done on a particular set of elite level athletes. E.g., some of the scientific studies on skating come out of places like the University of Delaware, which has professors who work in sport science and medicine, elite coaches who teach there, and has attracted a number of elite level skaters.

The hockey community has more or less come to consensus on the idea that lightweight boots & blades extend the amount of time a hockey player can remain optimally effective on the ice (for the most part, at elite levels, that is less than a minute - they work very hard and get tired fast). Likewise, racers favor lightweight running shoes. It sort of makes sense that you would tire yourself out more quickly if you keep having to lift the extra weight.

I convinced myself some time ago that relatively lightweight boots and skis made it easier for me to go long distances in cross country skiing - even for backcountry skiing, I stopped using heavy backcountry skis and boots and went back to lightweight beginner equipment. And I eventually chose lighter weight hiking boots, and even decided I was less likely to injure myself that way. And I concluded that regardless of paddle shape (e.g., European spoon vs wing vs Greenland stick) and composition, I could sea kayak the farthest on the lightest paddle I had. But those are all very much endurance sports - and my results are specific to me.

But this sort of thing could be very individual. A number of years ago a Harlick rep (who used to be their master boot maker) told me that Michael Weiss chose relatively heavy boots - presumably because he used the weight (more precisely the linear and angular momentum) of the boot (and presumably the blade) to help create jumps. The same might conceivably apply to spins - it seems to me that a lot of figure skating moves include transferring angular momentum from one body part to another. Of course he was a very strong athlete. That may or may not apply to you.

It shouldn't surprise anyone to learn that many things that occur in advertisements need to be taken with a grain of salt, and that not everyone performs best with the same equipment choices.

You could always take an empirical approach: try adding lightweight ankle weights, and see how that affects your jumps - but be careful - I wonder if significant extra weight and momentum, applied suddenly without training might not work well with your current technique or even create injury.

Given the kind of enthusiastic endorsements some elite skaters have given specific equipment, and the fact that they had professionally produced videos talking about its advantages that appear on equipment websites, its likely that some of them were given more than just free equipment. I know a figure skating director (who used to manage an ISI club region) who was given free blades (in that case parabolic blades), presumably in hopes that she would recommend them.

It is possible there are more important things to you about particular blades, like blade shape, blade compensition and metalurgy (which affects edge longevity and possibly glide resistance), and precisely how they are sharpened and maintained.

I promise you that blade companies and the merchants who sell them would be happy you were to buy many different types of blades and try them all! Especially if you tend to buy the most expensive blades they sell. And some coaches might tell you that spending money instead on extra lessons (from them) might help you better.

So it's up to you.

 

[Timskate]

Thank you for your input!

Could you please share the research you’re referring to? The only study I could find was published in 2022 (here’s the link again: https://www.tandfonline.com/doi/full/10.1080/14763141.2022.2063757). In this study, they also tested the shock-absorbing capabilities of different blades and found no significant difference between the Gold Seal Revolution blade and traditional full-metal blades. However, they tested a new shock-absorbing blade design that showed a significant reduction in landing impact forces by about 15%.

The company behind these blades is Blade Science, and I actually purchased their blades. For me, the shock-absorbing feature has been a game changer. I’ve always struggled with bad knees, but since switching to these blades, I no longer experience pain when jumping. Before this, I was using Gold Seal Revolution blades, but they didn’t help with my knee issues.

Regarding lightweight blades, the only scientific data I could find shows no improvement in jump height. This leads to two interesting points of discussion:

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1. Truthful Marketing Claims​

Marketing claims must be accurate, substantiated, and backed by evidence. For instance, if a product claims to enhance performance—like enabling "higher jumps" or "cushioned landings"—these statements should be supported by verifiable data. Misleading claims that influence a consumer's decision could potentially lead to lawsuits. In the U.S., the Federal Trade Commission (FTC) enforces truth-in-advertising laws.

For example:

• Red Bull (2014): The slogan "Red Bull gives you wings" led to a $13 million settlement when consumers argued the drink didn’t enhance physical or mental performance as advertised.
• Activia Yogurt (2010): Dannon claimed that Activia was "clinically proven" to regulate digestion and boost immunity. This led to a $45 million settlement after the claims were proven misleading.

Despite these precedents, no figure skating blade manufacturers appear to have faced lawsuits for advertising "higher jumps" or "cushioned landings," even though the available data suggests lightweight blades don’t improve jump height.

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2. Regulations on Equipment That Enhances Performance​

If lightweight blades genuinely increase jump height or enhance performance in other ways, and if these claims were backed by verifiable data by the manufacturers, shouldn’t they be banned from competitions?

I assume figure skating equipment must comply with certain technical regulations. If a piece of equipment provides an athlete with an unfair advantage, governing bodies should evaluate it and decide whether it should be allowed in competitions. This is similar to how other sports regulate equipment that could affect fairness.

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What are your thoughts on these points?

 

[Query]

That's probably the same study. I've not read it, only comments on it in other forums. It does mention Revolution blades.

A number of skaters in other forums have mentioned that they felt the Revolution blades reduced impact.

I assume you don't really believe most advertising claims of most things are true?

In the Red Bull case, I think it was pretty obvious that drinking Red Bull does not cause people to sprout actual wings. I would have thought it would be obvious to the typical listener that that was meant to be comical, not a study-backed claim. I mean, you don't actually think Geico has a talking lizard, do you?

But Red Bull has a lot of caffeine and sugar, both performance enhancing substances, though I don't think most sporting organizations ban either. So maybe it enhances sports performance, up to a point.

Red Bull sponsors a lot of sports events. Perhaps in a metaphorical sense that gives athletes wings?

I've seen the Blade Science website before. (I was looking for Skate Science, which is dead.) Do you think they act a bit like a spring, and store and release significant energy into jumps?

It's great that their blades help you.

I wonder if they could be considered "mechanical aids".

 

[Timskate]

Thanks for sharing your thoughts!

I believe that skaters claiming that Revolution blades reduce impacts may be influenced by various factors, such as receiving free blades from the company for promotional purposes. Empirical evidence, of course, carries more weight than anecdotal accounts or marketing claims.

I mentioned the Red Bull case as an example of how even seemingly ridiculous marketing claims can have legal implications for a company and be challenged by consumers. (By the way, caffeine is listed as a monitored substance in anti-doping regulations.) Of course, people don’t buy Red Bull expecting to fly, but they do purchase equipment based on claims that it will improve performance.

For instance, many skaters purchase lightweight blades because manufacturers claim they improve jump height. An even more serious claim is that the Gold Seal Revolution blades reduce landing impacts to prevent injuries. This is actually why I bought them years ago, only to discover later that the claim wasn’t true. My knees didn’t improve, even though I believed I was protected on the ice. Health-related claims like this are far more serious. Interestingly, I can still find these misleading claims on many reseller websites.

I’m not an expert in engineering, but I believe there is a significant difference between shock absorbers and springs. Blade Science blades incorporate shock absorbers that reduce landing impact. These absorbers are quite stiff, and I notice the effect only during landings, while my jump take-offs feel the same. The stiffness, take-off dynamics, and landing loads are thoroughly explained in the research paper.

This is similar to how running shoes incorporate a soft outsole to protect athletes, which is not considered a mechanical aid. From what I’ve read, designs combining materials like aluminum or carbon fiber with steel blades may provide mechanical advantages. For example, the Revolution blades claim to have a “flexible lightweight design improving jump height,” which clearly aims to enhance performance. On the other hand, Blade Science doesn’t make such claims and provides scientific data showing that jump height remains the same across different blades but landing impacts are significantly reduced with the shock absorbers.

I’d love to hear more opinions on this topic from the skating community. It’s a subject of discussion in one of my university courses.

 

[asimov]

need to factor in the weight, height of the skater. The heavier you are the less impact to you on jump. Solid blade vs light blade do feel different.

 

[Timskate]

That’s an excellent point, thank you!

Another factor to consider is that the larger the blade size, the greater the potential weight savings. At least, I believe this holds true for some lightweight blade models. For example, there should be a more significant weight difference between solid and lightweight blades in size 11 compared to size 8.

From the test results, skaters weighing between 57–82 kg (height 167–190 cm) showed no improvement in jump height. In other words, they achieved the same jump height using both traditional solid blades and lightweight blades. This weight range likely includes nearly all junior and senior male competitors, who are probably the target group for lightweight blades.

If lightweight blades improve jump height only for 'lighter' skaters, blade manufacturers should include a disclaimer stating that lightweight blades increase jump height only up to a certain skater weight (if this is true, of course). This could help them avoid potential legal challenges regarding their claims.

Regarding the shock-absorbing capability, I assume that the heavier the skater, the more dissipation of load you would expect to see. However, since no load reduction was observed in the study with the Revolution blade, this could be considered a false claim for all skaters. I’m not sure whether Blade Science blades reduce landing impact more effectively for heavier skaters, but their website offers shock absorbers with different stiffness levels for skaters of varying weights. It make sense that skater weight does play a role. In contrast, the carbon fiber body of the Revolution blade appears to be identical across sizes 8 to 11, meaning its stiffness doesn’t vary regardless of the skater’s weight.

Another very interesting finding from the study is worth noting. The skaters didn’t know which blades were mounted on their boots during the tests, as the blades were covered (a common practice in scientific experiments to ensure unbiased results). Skaters were then asked to share their subjective experiences with the researchers. Interestingly, they did not report feeling any difference in jump height or blade weight across the different blades.

Even more fascinating, one of the blades was repeated twice in the tests (randomly repeated), and more than half of the skaters reported feeling a difference in edge sharpness and blade profile, despite it being the exact same blade. This finding suggests that subjective perception cannot be fully trusted and is often influenced by prior knowledge of the equipment being used.

It’s possible that solid blades vs. lightweight blades feel different to you because you know what blades are mounted on your boots. However, if you were “blinded” to the blades—meaning you didn’t know which type was mounted—you might not recognize whether they are lightweight or solid. The difference is likely too small to detect and may be influenced by other factors, such as the overall weight of the boots and subjective bias. Does this make sense? The psychological influence of prior knowledge on equipment perception is a well-documented phenomenon and this idea apply to many other types of sports equipment as well.

 

[IceM]

The difference in weight we're talking about here is roughly the size of a glass of water. Does drinking a glass of water beforehand make you unable to jump high? I'd hope not.

Ok, the weight is at the end of your legs, so even a few hundred grams here and there could affect some aspects where you are having to suspend your leg against a lot of torque. That doesn't apply in jumps.

As to the benefits of Revolution style blade compared to a regular Gold Seal, there really isn't any (but there are some drawbacks). The thinner runner (blade) and shorter tail of the Rev is up to personal preference, and not related to the design itself.

The one thing these lightweight designs enable, is the use of better and more expensive metals in the actual runner (part of the blade you skate on) by replacing the majority of the blade with cheaper aluminum or carbon fiber chassis. John Wilson is only doing this with their Phoenix line, although those blades are almost impossible to find anywhere.

 

[Query]

Ok, the weight is at the end of your legs, so even a few hundred grams here and there could affect some aspects where you are having to suspend your leg against a lot of torque. That doesn't apply in jumps.

I guess you mean it would make moves like shoot the duck, spiral, sit spin, pancake spin & camel spin harder... I hadn't thought of that. That makes a lot of sense!

Even trying my dubious spiral makes me fight the weight of my leg & boot & blade - which I do notice. It's a lot easier for me to stretch with my leg up on something (like the walls to the hockey player box). For me, a lot of the resistance is due to flexibility limits. But it sure would be easier if my leg, boot & blade weighed nothing.

 

[Timskate]

Thank you for sharing your thoughts!

I am particularly interested in manufacturers' and resellers' claims that lightweight blades improve jump height and the skating community's perspective on these assertions. It appears that many within the community recognize these claims as unsubstantiated. Despite this, such misinformation continues to circulate among coaches, parents, and skaters.

In other sports like motorsports, athletics, and ice hockey, consumers tend to be more critical and demand data to support performance claims. If a company's assertions are proven false, its reputation can suffer significantly. However, in figure skating, major blade manufacturers collectively propagate these unverified claims, and the community seems to accept them. This may be due to the limited number of companies specializing in figure skating equipment, allowing them to make such assertions without substantial evidence.

Regarding materials, according to the referenced study, the steel used for the Gold Seal Revolution blade is carbon steel (AISI 1075), which is also found in less expensive beginner blades like Riedell's Volant. Therefore, a higher cost doesn't necessarily equate to superior steel.

Concerning thinner tails, I read that the thinner tail of the blade can be more challenging to sharpen properly, potentially disadvantaging the skater if not done correctly. The purported benefit of a thinner tail is to reduce friction and enhance speed. However, if this were true, it would likely be adopted in ice hockey as well. This raises questions about the validity of such claims, as speed tests seem quite easy to conduct, yet I could not find any data supporting this.

As previously discussed here, having slightly more weight at the distal portion of the leg can increase linear and angular momentum, potentially aiding in higher jumps and faster rotations (spins and jumps). This might explain why many Russian skaters prefer traditional blades over lightweight versions. The weight difference between lightweight and traditional blades is minimal—between 69 grams and 144 grams (2.43 - 5.08 ounces) for a size 10.25 blade (as measured in the study)—so the overall impact on performance is likely negligible. For smaller blade sizes, the weight savings would be even less. It's comparable to questioning whether removing a watch or jewelry from your wrist would improve spins, jump height, or spirals; the effect would probably be insignificant.

In my opinion, we would see more innovation in figure skating if the community critically evaluated such marketing claims and relied on evidence-based information when selecting equipment. This would push companies to properly test their equipment, as currently, it seems they can make unverified claims without providing data, resulting in minimal drive for actual improvement. I would love to have a blade or boot that genuinely increases jump height and overall performance. Today, it feels like equipment still mostly limits and restricts foot movement. Weight saving is ofcourse also important but the curent weight saving is minimal and unlikely to significantly impact performance in any way.

 

[Query]

In other sports like motorsports, athletics, and ice hockey, consumers tend to be more critical and demand data to support performance claims.

You see many dubious claims regarding equipment in hockey - e.g., claims that a company's products (like heated blades) are used by NHL players. In reality, they give the equipment to NHL players or team, which sometimes try them out - and reject most of them. Another example: I'm not sure if any NHL players currently use flat bottom V sharpening, but if so, it isn't many.

Concerning thinner tails, I read that the thinner tail of the blade can be more challenging to sharpen properly, potentially disadvantaging the skater if not done correctly. The purported benefit of a thinner tail is to reduce friction and enhance speed. However, if this were true, it would likely be adopted in ice hockey as well.

Hockey blades are thinner than figure blades everywhere, not just at the tail. And they are faster. Though that might also be because they have a flatter rocker in the center, which both reduces drag, and also allows skilled hockey skater to push harder. Speed skating blades are even thinner. Many ice dancers will tell you that MK Dance blades are faster than other figure skating blades, despite the shorter length, because they are ground thinner.

But of course, like you imply, that is different from proving that tapered blades (which is what Scarlet skater and some others call blades that are thinner at the back than the front) are faster than a blade with the same average width.

Perhaps you would like to test this theory? Say, for example, by moving blades on ice, and measuring the drag force.

Of course there are many variables which might affect the result. E.g., speed, sharpening style. Ice temperature and roughness. (Consider: a wider blade might ride higher up front, so degree of surface penetration might matter. Also, friction depends a lot on temperature and roughness.) Also, figure skates and hockey blades are different enough, a result that applies to one might not apply to the other. All of which complicates testing.

 

[Flying Feijoa]

Blind studies and placebo effects are fairly standard scientific concepts, but it's nice to see another study in the relatively sparse field of figure skating sports science.
With regards specifically to injury prevention, it's not necessarily straightforward to extrapolate shock absorption under this setup (vertical drop) to this issue because other factors (e.g. skating technique/physical conditioning/body structure) could have a similar if not bigger impact.
For instance:
-chronic underrotation (skating technique) can strain the ankle ligaments on jump landings, but could be mitigated somewhat by a stiffer boot (equipment) and strengthening the ankle muscles (physical conditioning).
-however, an excessively stiff boot can affect landing biomechanics by hindering ankle dorsiflexion, which might potentially contribute to repetitive strain injuries e.g. to the back or knees.
-structural features like a high Q angle can predispose individuals to knee issues such as patellofemoral syndrome or ACL tears.
If these other conditions remain equal, then a 15% reduction in landing force might of course help reduce knee pain, but I think choice of blade may not be as critical as e.g. the boot or physiotherapy.

 

[Timskate]

You see many dubious claims regarding equipment in hockey - e.g., claims that a company's products (like heated blades) are used by NHL players. In reality, they give the equipment to NHL players or team, which sometimes try them out - and reject most of them. Another example: I'm not sure if any NHL players currently use flat bottom V sharpening, but if so, it isn't many.



Hockey blades are thinner than figure blades everywhere, not just at the tail. And they are faster. Though that might also be because they have a flatter rocker in the center, which both reduces drag, and also allows skilled hockey skater to push harder. Speed skating blades are even thinner. Many ice dancers will tell you that MK Dance blades are faster than other figure skating blades, despite the shorter length, because they are ground thinner.

But of course, like you imply, that is different from proving that tapered blades (which is what Scarlet skater and some others call blades that are thinner at the back than the front) are faster than a blade with the same average width.

Perhaps you would like to test this theory? Say, for example, by moving blades on ice, and measuring the drag force.

Of course there are many variables which might affect the result. E.g., speed, sharpening style. Ice temperature and roughness. (Consider: a wider blade might ride higher up front, so degree of surface penetration might matter. Also, friction depends a lot on temperature and roughness.) Also, figure skates and hockey blades are different enough, a result that applies to one might not apply to the other. All of which complicates testing.

Thank you again! For not being an expert or elite athlete, you seem to have a lot of knowledge in this field. Thanks!
While dubious claims exist in all industries, it's uncommon for nearly all manufacturers within a field to propagate the same misleading information. In figure skating, manufacturers assert the same enhanced performance in light weight blades without providing supporting evidence.
Is it acceptable for consumers to be misled in this manner? Parents may invest in expensive blades, believing they will improve their children's performance, only to find these claims unsubstantiated.
You mentioned that hockey blades or thinner blades are faster. Have you encountered any test data supporting this or just opinions, such as those from ice dancers? And why only MK blades, not other thin dance blade? Without concrete data, sharing such information contributes to misinformation.
During skating, athletes primarily use the inside or outside edges, except when gliding straight over both edges, which is rare, especially among ice dancers. Moreover, having only the blade's end thinner seems illogical, as skaters predominantly use the front part or half of the blade.
Testing this theory would also require blades of identical length, weight, and profile, differing only in width. Comparisons with hockey blades, which have different profiles, or speed skates, which are much longer, are inadequate. Conducting such tests is challenging, as you said, due to variables like ice temperature, sharpening etc.. However, having skaters unaware of blade thickness skate a pattern (not just straight forward) on different blades and comparing times could yield insights. Alternatively, computer simulations could evaluate the effect of drag force over a 100-meter glide on blades of varying thickness. Given the dynamic nature of figure skating and hockey, with constant speed and direction changes, and minimal straight-edge skating, it's reasonable to question these marketing claims as tactics to extract more money from customers.

 

[Timskate]

Blind studies and placebo effects are fairly standard scientific concepts, but it's nice to see another study in the relatively sparse field of figure skating sports science.
With regards specifically to injury prevention, it's not necessarily straightforward to extrapolate shock absorption under this setup (vertical drop) to this issue because other factors (e.g. skating technique/physical conditioning/body structure) could have a similar if not bigger impact.
For instance:
-chronic underrotation (skating technique) can strain the ankle ligaments on jump landings, but could be mitigated somewhat by a stiffer boot (equipment) and strengthening the ankle muscles (physical conditioning).
-however, an excessively stiff boot can affect landing biomechanics by hindering ankle dorsiflexion, which might potentially contribute to repetitive strain injuries e.g. to the back or knees.
-structural features like a high Q angle can predispose individuals to knee issues such as patellofemoral syndrome or ACL tears.
If these other conditions remain equal, then a 15% reduction in landing force might of course help reduce knee pain, but I think choice of blade may not be as critical as e.g. the boot or physiotherapy.

I don’t think it was just a drop test, the skaters in the study performed a rotational movement to simulate the dynamics of figure skating landings. Right, while factors such as boot stiffness, athlete strength, flexibility, and technique play significant roles, a 15% reduction in load can significantly benefit skaters. Considering that landing impacts can range from five to ten times a skater's body weight, reducing each landing's impact by 15% substantially lessens the strain on the body, especially given the high frequency of jumps performed year-round at very young age.

Studies indicate that overuse injuries are more prevalent than acute injuries among skaters, with landing impact forces being a contributing factor. The studies shows that these injuries predominantly affect the landing leg. Using a blade that dissipates impact forces by 15% is a significant advancement in injury prevention and should be a key consideration when selecting equipment. Personally, I've noticed a clear difference on the ice, and my pain disappeared after switching to shock-absorbing blades.

 

[Query]

While I'm not a very good skater, I can speak somewhat from personal experience. When I switched from Coronation Ace to MK Dance, I sped up a lot. And when I switched from MK Dance to Ultima Matrix 1 Dance, Ultima Matrix 1 Supreme and Ultima Matrix 1 Synchro, all wider than MK Dance at the bottom, I slowed down again.

But there are a lot of other factors. For one, the Coronation Ace blades were warped, to the extent that they got very hot when I skated. And there are other factors.

I have skated a little on hockey skates. Despite my relative inexperience, they were definitely faster. And on (rather outdated) short & long track speed skates. (BTW, this was before "clap skates" were used to extend the time the runner is on the ice for long track speed skates.) Faster still. But the hockey skates also had a flatter rocker in the center, as well as a longer ROH, and the speed skates had a still flatter rocker, and no hollow at all. This isn't just psychological. I remember roughly timing how long it took me to go the length of the rink.

The speed skating community does a lot of testing of minor changes to blade shape. As tends to be true in any racing sport. Because races are often decided by .01 seconds or less. So I suspect they are pretty close to optimal within the limits of the rules of the sport. Modern short and long track speed skates are very, very thin. To the extend that heavy skaters sometimes flatten the rocker substantially due to their weight. (I don't know much about Nordic skates, such as are used on frozen lakes and cross country - but as best as I can find out, they generally have no rocker curvature.) But like hockey skates, the speed skating community (this might only apply to short track) seems to have moved towards continuously varied rocker lengths, flatter in the center. But AFAIK, speed skaters do no taper blades at this time.

The physics of ice skating are not well enough understood to numerically simulate what goes on to a high enough accuracy to determine what design is best. Even hydrodynamics of ships aren't modeled very accurately - real world tests are still needed to design them. And that's after pouring an extraordinary amount of money and resources into the problem - to an extent, every new ship design is an experiment. Whereas no one is willing to poor that kind of money into understanding and modelling the physics of skating.

Speed and power are well rewarded by judges in figure skating. But they aren't the only factor. Figure skating judges also reward artistry, and the ability to do various tricks, while meeting the technical and aesthetic standards of the sport. So the fastest blades might not always be the best. As an example, thin blades like MK Dance make it harder to stabilize spins, and maybe harder to stabilize jump landings.

Consider how different speed skating clothing is from figure skating. Speed skaters tend to wear skin tight outfits designed to minimize aerodynamic drag. Sometimes, like swimmers, they shave their heads. Figure skating ladies often have their dresses designed to create elaborate standing wave patterns while they spin, and so on. Sometimes they play with various effects on long hair. These are not what they would do if speed was the only goal.

 

[Timskate]

For one, the Coronation Ace blades were warped, to the extent that they got very hot when I skated.

Thank you for sharing your personal experience with different blades.

As the study I shared earlier in this discussion showed, subjective perception cannot be fully trusted and is often influenced by prior knowledge of the equipment being used. Notably, more than half of the elite skaters who participated in the study—individuals who should have the best feel for their blades—perceived differences in edge sharpness and blade profile when using identical blades. Therefore, feeling faster doesn't necessarily mean you were actually faster.

You make a good point regarding the skater's weight; it makes sense that a thinner blade would cut deeper into the ice, potentially slowing the skater down.

Once again, manufacturers have not conducted tests to evaluate the effect of blade thickness on speed, similar to unverified claims about jump height and shock-absorbing capabilities. These unsupported assertions mislead consumers and constitute unfair marketing practices. Imagine purchasing a phone advertised to have a 24-hour battery life, only to find it lasts just 12 hours, the same as your old phone. With blades, it's certainly harder to prove that the function is fake, but that doesn't mean manufacturers can claim whatever they want. At the very least, an effort to test these aspects would be valuable, but there seems to be a lack of such approach, which is part of the problem.

Additionally, I find it hard to believe that your blade became 'very hot' during skating. Were you melting the ice beneath you? It makes me wonder what speeds you were skating at for a metal blade to become so hot from friction against the ice.

Achieving a skate blade temperature of just 10°C (50°F) through frictional heating during skating is highly improbable. Studies indicate that even at high speeds, the temperature at the blade-ice interface remains just below 0°C (32°F), sufficient to create a lubricating meltwater layer but not to significantly heat the blade. The efficient heat dissipation properties of steel and the continuous cooling effect of the ice prevent substantial temperature increases. Therefore, even with prolonged skating at speeds of 40–50 km/h (approximately 11–14 m/s or 25–31 mph), the blade's temperature would not approach 10°C. The cooling effect of the ice and the thermal conductivity of the blade material maintain the blade at temperatures near the freezing point of water.

 

[Query]

I wasn't going 40-50 km/h, or even close. And those blades did get hot, though not hot enough to burn me. That's what I know. I haven't duplicate this since - I have wondered whether some of the friction occurred by dragging the toepick. And I don't intend to deliberately warp my blades.

The question of whether there is a liquid water layer on top of the ice when you skate has been debated a lot. In particular, ice at ice rink temperatures is substantially more slippery than water - in fact much more slippery, AFAIK, than any other solid or liquid. Except for "superfluids" (like Helium 3 within a few degrees of absolute zero). (Alas, skating on helium 3 superfluid would be too dangerous, because it is so cold, and because of the skin effect.) Which is why "artificial ice" rinks made by lubricating plastic aren't nearly as much fun as real ice.

For a while, one theory was that there was a "two dimensional liquid" layer, in which motions were confined to a plane. I'm not sure what happened to that theory.

There was a study that indicated that the top several molecules of ice that is a little below the freezing point, do not have crystalline order. (I assume they used x-ray diffraction, but am not sure.) It makes some sense - in particular the top layer would not have its structure locked in by nearby bonds from on top. However, the study did not have a moving metal blade against the surface. The study theorized there might actually be several layers with different structures in the interface. And it contained comments that sought to convince people to fund additional research, on the theory that if one understand the underlying structure, one could create better lubricants.

A few centuries ago a physicist theorized that pressure induced melting was responsible for the slipperiness of ice, because ice is less dense than water, so sufficient pressure should force it into a liquid state. And you still see that theory in many introductory physics text books. But 3 months later another physicist demonstrated that the change in melting point that would be expected wasn't sufficient to melt the ice at ice rink temperatures - i.e. that skating doesn't create enough pressure. And in fact, possibly outside parts of Antarctica (which has areas with extremely thick ice), for the most part even most glaciers aren't thick enough to generate enough pressure to do that - many glaciers show wear patterns consistent with sliding as a solid.

As best I understand the principles, to have such a slippery surface, the electrons in one layers must not interact much with the electrons in the layers around them. While that is presumably a boundary layer effect that involves quantum mechanics, there have been multiple ideas of how that could happen. (Perhaps somewhat like graphite - except graphite isn't nearly as slippery.) But that might also mean that the frictional heat does not conduct well into the ice, because it would be conducted via electron interactions - so maybe that's why my warped blades were able to stay hot.

If only someone were to put a few billion dollars into researching the structure of ice under skate blades, we could maybe answer a lot of these questions in a definitive way. In the mean time, I think some of the research is self-funded - which limits how far they can go.

Anyway, this is pretty far afield from the original question.

 

[tstop4me]

You make a good point regarding the skater's weight; it makes sense that a thinner blade would cut deeper into the ice, potentially slowing the skater down.

I assume you reach this conclusion along the following line of reasoning. Pressure Exerted by the Blade on the Ice = (Total Weight of Skater and Gear)/(Contact Area of Blade on Ice). The greater the pressure, the deeper the cut. The contact area is a function of the thickness of the blade. The thinner the blade, the smaller the contact area. The smaller the contact area, the greater the pressure.

But note that that "the contact area is a function of the thickness of the blade" holds only for a limited scenario: for a speed skate blade ground with a flat bottom (no hollow) oriented such that the flat bottom is in full contact with the surface of the ice; i.e., the sides of the blade are orthogonal to the plane of the ice. If orthogonality is not strictly maintained, the contact area will no longer be dependent on the thickness of the blade (here I'm excluding ice so soft that the blade sinks in).

Figure skate blades are ground with a hollow to produce two distinct edges, an inside edge and an outside edge. During a straight glide on a clean, proper ice surface, the blade will leave a double trace | | (two traces, one from each edge, spaced apart); not a single wide trace with a width approximately equal to the thickness of the blade. So the contact area is not a function of the thickness of the blade (here I'm excluding ice so soft that the blade sinks in). And of course, during a curved glide on a single edge, the contact area is not a function of the thickness of the blade.

With blades ground with a hollow, you need to take into consideration the blade edge angles, and the dependence of the blade edge angles on the radius of hollow (ROH) and the blade thickness. Many skaters know that they can vary the sharpness of the edges by changing the ROH. Many don't realize, however, that for a fixed ROH, the degree of sharpness will vary with the blade thickness. This has been discussed in a previous thread: https://www.goldenskate.com/forum/threads/how-different-radius-of-hollow-affect-skating.81787/. Here are my key posts from that thread (to simplify the discussion, I'm describing blades with no side honing, but the basic concept holds for other geometries):

Not sure what you mean by effective contact surface in this instance. But I view the scenario in terms on the included edge angles. Think of the inside skate edge and the outside skate edge in terms of the edge of a knife. Each skate edge is defined by the intersection of two surfaces: one surface is the curved hollow, the other surface is the flat exterior surface of the skate blade (outside or inside exterior surface). The included angle at the intersection defines how sharp the skate edge is. Just as in a knife blade, the smaller the included angle, the sharper the skate edge. For a fixed value of the ROH, the included angle varies with the thickness of the skate blade: the thicker the blade, the smaller the included angle and the sharper the skate edge.

In a tapered skate blade, the thickness is greatest near the picks, and decreases progressively towards the heel; therefore, the skate edges are sharpest near the front of the blade, and gets progressively less sharp towards the rear of the blade. This provides extra bite for maneuvers (such as turns and entrances to spins) that use the front of the blade; and extra glide for maneuvers that use the middle and rear of the blade.

For a parabolic blade, the blade is thicker near the pick and heel, and thinner near the middle. This provides a more longitudinally symmetric blade: more bite towards the front and heel; and extra glide near the middle.

I'll try to explain as best as I can using keyboard characters, in lieu of a drawing. Suppose you're holding one skate in front of you, edges facing you, vertically oriented with picks on the top, heel on the bottom. Imagine the edges projected onto a plane, such as a flat screen (as if you were viewing them on a camera LCD screen).

* With parallel edges, the outside and inside edges are configured as such: ||. The edges are straight lines, and the lines are parallel. The thickness of the blade (transverse distance measured between the outside and inside edges) is nominally constant along the length of the blade.

* With tapered edges, the outside and inside edges are configured as such: \ / (greatly exaggerated). The edges are straight lines, but the lines are not parallel, The thickness of the blade progressively decreases from near the picks (thickest) to the heel (thinnest).

* With parabolic edges, the outside and inside edges are configured as such: ) ( (greatly exaggerated). The edges are concave curves. The blades are thicker near the picks and the heel and thinner near the middle.

* Blade thickness (for a constant ROH, the edge angles vary as a function of thickness; for a fixed value of ROH, the edges on a thicker blade will be sharper than the edges on a thinner blade; the thickness of freestyle blades do vary; this is of more particular consequence for slimline/thinline dance blades (to get the same sharpness on a thinner dance blade as on a thicker freestyle blade, the ROH for the dance blade needs to be smaller than the ROH for the freestyle blade);

 

[Query]

I wonder though if tapered figure skate blades might actually make sense from a speed perspective. In particular, having a fat blade up front may cause that part of the blade to sink in less, which might cause the blade to do the equivalent of hydroplaning more, and ride higher over the surface in general, due to generated lift. I'm thinking in terms of parallels to relatively low power (e.g., human powered) hydroplaning whitewater play boats, which are pretty fat, including up front. (Note: I am unfamiliar with recent the newest generations of human powered hydroplaning boats, which have greatly extended the distances that human powered boats can hydroplane. But they aren't playboats - they are purely designed for speed over specific distances ranges - nothing like figure skates, which are designed to play. And water is a lot softer than ice.)

But I'm not sure that is needed. After all, many skaters tend to move a lot faster over the ice than most paddlers move over the water. Besides, we are planing without that - clearly we do not sink in deep enough for Archimedes principle to apply. And if tapering made sense for speed skating, speed skates ought to be tapered, and AFAIK, they are not.

tstop4me, short and long track speed skates do not usually have full contact with the bottom, because they do have rocker curvature. (See https://www.danielyeow.com/2011/inline-to-ice-1 for some speed skate rocker curvatures). But I'm not sure how much that affects your argument. Especially since this forum isn't devoted to speed skating.

Anyway, I doubt if discussions of physics theory interests many people here. And I'm guilty of contributing to that, despite admitting that there remain significant open questions about the physics of skating. If testing is to be done, to accurately reflect reality, I believe that testing should be empirical, rather than based on simulations derived from imperfect theory.

But I bet that whatever testing we tried to do for ourselves, most skaters would continue to think their current blades worked well for them. Or assume that whatever their favorite world class skater uses, would be best for them too. Or that their coach knows best.

Maybe blade choices are more about marketing than physics and engineering?

The o.p.'s original question was about how the weight of blades affected jumps. While speed over the ice affects jumps too, we don't have any convincing evidence here that faster blades are better for jumps. MK Dance blades are ground "thinline" primarily to allow fast edge changes, and secondarily for speed, but not to create better jumps. AFAIK, they genuinely dominate the elite ice dance world, much more than any single blade design dominates the elite freestyle world, but are not commonly used for freestyle. Probably for good reasons.