Biomechanics of figure skating
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Russia’s Mishin Is Dean of Coaches | Skate Today
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Coach Alexei Mishin has written several books on the biomechanics of jumps and figure skating.
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I think they're only available in Russian though, which is a shame because they look like they'd be fun to read or...considering I'm terrible at science and stuff probably not. Still it'd be interesting!Russia’s Mishin Is Dean of Coaches | Skate Today
Coach Alexei Mishin has written several books on the biomechanics of jumps and figure skating.
- Joined
- Jul 26, 2003
The article says they were available in "Russia, Germany, China, Japan and several other countries." Amazon does not show it though.
Another book:
Another book:
Breaking the Ice: Breaking Down the Science of Figure Skating Jumps for Effective Training and Injury Prevention , Paradi, Sophie - Amazon.com
Breaking the Ice: Breaking Down the Science of Figure Skating Jumps for Effective Training and Injury Prevention - Kindle edition by Paradi, Sophie. Download it once and read it on your Kindle device, PC, phones or tablets. Use features like bookmarks, note taking and highlighting while reading...
www.amazon.com
I'll probably order that Paradi's book. Haven't found Mishin's yet. In the meantime, I share you my calculation... 
If you consider how many spins you can do during a jump, the most important thing is of course how fast you spin, i.e., angular velocity. Equally important is the time you are in air. I'll dedicate this post to the time you are in air, because I don't know what factors affect the skater's angular velocity.
The time you are in air for any jump, not just figure skating jump, is t = 2 vmax/g where vmax is your maximal vertical velocity and g is the gravitational acceleration. For jumping with your legs, the equation can be written as
t = (2/g)( 2s (-g+F/m) )^0.5 ,
pardon my maths, I couldn't start my LaTeX. In this equation, g is still the gravitational acceleration, s is the leg extension length, F is the force and m is the mass of the skater.
Judging by this equation, I see little point in the extreme weight control some skaters seem to practice. Namely, if you are a fit young athlete, you can easily increase your leg's strength by 50%, but you can't decrease your weight by 33% which would have an equal effect. If I wanted to become a "jump machine", I would just consider leg press.
Opinions welcome!
If you consider how many spins you can do during a jump, the most important thing is of course how fast you spin, i.e., angular velocity. Equally important is the time you are in air. I'll dedicate this post to the time you are in air, because I don't know what factors affect the skater's angular velocity.
The time you are in air for any jump, not just figure skating jump, is t = 2 vmax/g where vmax is your maximal vertical velocity and g is the gravitational acceleration. For jumping with your legs, the equation can be written as
t = (2/g)( 2s (-g+F/m) )^0.5 ,
pardon my maths, I couldn't start my LaTeX. In this equation, g is still the gravitational acceleration, s is the leg extension length, F is the force and m is the mass of the skater.
Judging by this equation, I see little point in the extreme weight control some skaters seem to practice. Namely, if you are a fit young athlete, you can easily increase your leg's strength by 50%, but you can't decrease your weight by 33% which would have an equal effect. If I wanted to become a "jump machine", I would just consider leg press.
Opinions welcome!
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- Jan 9, 2017
We don't do leg press and high weight training much as elite athletes b/c it would make the legs bulky and goal for figure skaters is long and lean strong muscle, not bulk. Hence why we focus on non bulk strength training, agility, as well as yoga, pilates, resistance training, etc. Balance lean and protein rich diet are usually way to go. Drinking LOTS of water, etc.I'll probably order that Paradi's book. Haven't found Mishin's yet. In the meantime, I share you my calculation...
If you consider how many spins you can do during a jump, the most important thing is of course how fast you spin, i.e., angular velocity. Equally important is the time you are in air. I'll dedicate this post to the time you are in air, because I don't know what factors affect the skater's angular velocity.
The time you are in air for any jump, not just figure skating jump, is t = 2 vmax/g where vmax is your maximal vertical velocity and g is the gravitational acceleration. For jumping with your legs, the equation can be written as
t = (2/g)( 2s (-g+F/m) )^0.5 ,
pardon my maths, I couldn't start my LaTeX. In this equation, g is still the gravitational acceleration, s is the leg extension length, F is the force and m is the mass of the skater.
Judging by this equation, I see little point in the extreme weight control some skaters seem to practice. Namely, if you are a fit young athlete, you can easily increase your leg's strength by 50%, but you can't decrease your weight by 33% which would have an equal effect. If I wanted to become a "jump machine", I would just consider leg press.
Opinions welcome!
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- Sep 22, 2019
I also see little point in it, but I am guessing those skaters (or their coaches) are not very good at strength training. A lot of coaches with reputation of relying on low body weight also seem to produce skaters who don't jump particularly high and have technique issues. Weight loss is a blunt force tactic, while neuromuscular development requires a bit more finesse
Apart from body conditioning (developing high-power, fast-twitch, low-bulk muscles), there's also on-ice technique which is a bit harder to simulate in a reductionist engineering scenario. I know you intentionally left out angular velocity - the take-off stage determines the initial angular momentum as well as air time. Once you're in the air then it's basically an isolated system so angular velocity can only be increased by reducing the moment of inertia (pulling in the limbs). Most skaters nowadays try to maximise this pulled-in phase by snapping into the tight rotational position as soon as possible (versus the old approach which focuses more on air time at the cost of time spent at max angular velocity: using the limbs to gain height and snapping in later).
What goes on a few seconds before the jump is also important - if you're good at generating linear speed, you will have more air time provided you can efficiently convert it to vertical height (again, via good takeoff technique - timing, body position). Skating speed is affected by stroking efficiency (body alignment, how you lean into edges and maximise power from each push etc. - basically, core strength and coordination rather than raw leg power).
Since English is not my native tongue, I don't know if you can call skaters athletes. Can you? Anyway, is there any rational reason to aim for long and lean muscles? I don't know how you can even increase the muscle length, strictly speaking.
I appreciate your point. The equation I derived is just a simple mechanistic model. It just serves to illustrate the importance of the F/m ratio, a ratio which can be improved at the gym. It's tacitly assumed that F is the vertical component of the force and s is the vertical projection of the leg extension. Regarding the air time, it would be optimal to push directly upwards, but that may be impossible due to various reasons, like the need to generate the spins and to maintain balance before the jump. So, apart from the gym, on-ice training also improves the ratio.I also see little point in it, but I am guessing those skaters (or their coaches) are not very good at strength training. A lot of coaches with reputation of relying on low body weight also seem to produce skaters who don't jump particularly high and have technique issues. Weight loss is a blunt force tactic, while neuromuscular development requires a bit more finesse
Apart from body conditioning (developing high-power, fast-twitch, low-bulk muscles), there's also on-ice technique which is a bit harder to simulate in a reductionist engineering scenario. I know you intentionally left out angular velocity - the take-off stage determines the initial angular momentum as well as air time. Once you're in the air then it's basically an isolated system so angular velocity can only be increased by reducing the moment of inertia (pulling in the limbs). Most skaters nowadays try to maximise this pulled-in phase by snapping into the tight rotational position as soon as possible (versus the old approach which focuses more on air time at the cost of time spent at max angular velocity: using the limbs to gain height and snapping in later).
What goes on a few seconds before the jump is also important - if you're good at generating linear speed, you will have more air time provided you can efficiently convert it to vertical height (again, via good takeoff technique - timing, body position). Skating speed is affected by stroking efficiency (body alignment, how you lean into edges and maximise power from each push etc. - basically, core strength and coordination rather than raw leg power).
Sports can be an endless goldmine of engineering problems. If you wanted to go down that way, you could build a more detailed model involving a model of the skating human body, and then you would go for computer simulations. Just a stupid question to conclude: Isn't it so that in FS, you use one leg to push upwards and the other one to generate the spins? In all jumps?
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- Oct 22, 2005
YES, skaters are DEFINITELY athletes. Skating requires more athleticism than almost any other sport in a coordinated manner you don't see in most sports. Probably the only sport requiring more athleticism is gymnastics.
"Long and lean muscles" insinuates you are building and relying on type 2 muscle fibers versus type 1, which tend to be bulkier. Type 2 muscle fibers contract faster creating that explosion on jumps and tend to give someone that long and lean look. Type 1 muscle fibers are endurance sport typically and tend to be bulkier.
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- Sep 22, 2019
No, both legs contribute somewhat to both roles. It also varies between jumps. With edge jumps the same leg you push off with is also generating angular momentum because it is being used to create a tightening entry edge, and as for the free leg, before it snaps in to increase rotational speed it goes up during takeoff which helps height too (not sure how to describe but I guess it raises the centre of gravity). With toe jumps you vault up from an edge via a toepick - you are pushing down on the ice with both legs although your weight shifts to the picking leg at the final moment (think of getting up from a lunge that travels backward). With toe jumps, torque can come from the edge you jump off (esp. toeloops) as well as the picking leg (although pivoting on the toepick for lutz/flip is ideally limited) but generally they rely more on pulling the limbs in after takeoff (free leg + arms) to generate rotation.
Disclaimer: not a coach, I just skate for fun and have a background in science.
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- Jan 9, 2017
Yes, we are athletes to the highest degree and English as your first language or not: Many of us who are ATHLETES of this sport are incredibly offended (I can see I am not the only one on this thread). From reading replies to you on the rest of the thread, the conclusion is that you should really read up on the sport and be open-minded about it in order to even think of doing anything with biomechanics regarding it. Otherwise, just a kind suggestion to maybe concentrate on a sport you know better. Just my humble opinion.
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Ooooo YAY FOR SCIENCE! Ha. I have that book that was mentioned (I didn't read all the comments) - it's good in terms of a starting point (but meh on some of the topics), especially for citations. If you have academic access, look up Deborah King's articles (she has data from skates mounted with sensors), or Sarah Ridge in Utah. There's another guy in Delaware but I'm blanking on his name. I love talking about some of these things, so if you ever want to chat, let me know! I'm a neuroscientist, but weak on physics (like, I get it enough to think generally about issues, but not in enough detail to really sensibly discuss it - I'm still learning).
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- Oct 22, 2005
This is incorrect in terms of describing the mechanics of jumps (both edge and toe jumps) in many respects. How the body is used is more of a function of change of rotational axis in the jump or no change of rotational axis. If you don't understand this piece of figure skating jumps and biomechanics, your "math" is COMPLETELY incorrect instead of mostly incorrect and your understanding is lacking.
I think there is a misconception about weight training automatically bulking; stabilization of joints by weight training is huge and part of the design of general athletic conditioning, which should easily contribute to better efficiency in transition between horizontal and vertical velocity. But like I said, I'm not a physicist - I'm a biologist.
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- Jan 9, 2017
Just saying, I never said that all weight training led to major bulking of muscles. We do use different forms of weight training, but in a way that it does NOT bulk our muscles.
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- Sep 22, 2019
Excuse me, I didn't mention any maths, and I'm not the engineer in this thread (it's the original poster). I took pains to state that I'm not a coach nor a high-level skater - whatever I said is how my own coach explains things when we're working on doubles - so it's not like there is a need to put me in my place.
I don't think we are on the same page about what the poster was asking. Yes, change (or not) in rotational axis is a characteristic that makes Loop/Flip/Lutz mechanically similar compared to Axel/Toe/Sal, but the poster is not a skater (not sure if they actually can tell between the six jumps) and was asking if "one leg pushes upwards and the other generates spins". I interpreted this as being a question whether each leg is solely responsible for either height or rotation, so decided to address it by explaining how it doesn't hold true neither for edge jumps (with the entry edge rotation) nor toe jumps (with the weight transfer from skating to picking leg). If you do axel/toe/sal then the swingthrough and mid-air shift to landing leg contributes significantly to rotation, so the question could have also been addressed that way.
Some skaters prefer no-axis-change jumps over axis-change jumps (me included), others prefer edge jumps over toe jumps. What characteristic you find the most salient is rather subjective. Some coaches teach kids loop before toeloop or vice versa; approaches also differ on how they communicate the concept of pre-rotation (or lack thereof).
@kolyadafan2002 sorry to bring you into this, but I noticed you have a knack for explaining skating technique in words
We are going on a tangent that may be of little interest to the OP, but nevertheless would you be able to weigh in on whether I committed a cardinal sin in my explanation or not?Are you certain? Endurance athletes don't typically tend to be bulky.
