The biggest 2010 surfing event in the US was recently completed in perfect 6 foot waves at Trestles in Southern California. The surfing was innovative and exciting with technical and high flying performances, elevating surfing to a mesmerizing and progressive spectator sport.
This was the first surf event to use the new competition format, pitting the worlds top 32 surfers and 4 qualifiers against each other. If you want to find out more about the surfing World Championship Tour check out this video or head to the ASP Surfing website. The new format and fantastic waves brought the best out of many surfers on the tour.
Dane Reynolds and Jordy Smith were stand out performers, particularly in the air and that's where we want to go in this blog. Just like basketball slam dunk competitions, the higher the aerial maneuver the more exciting and better it is. Of course if the surfer does not land and ride out then it cannot count (similar to a missed basket in an attempted slam). The surfing judging criteria do not specify height in an aerial move as a criteria, but height above the wave definitely makes the move look more difficult.
In the video we have Dane and Jordy performing aerial moves at the Trestles Hurley Pro. Dane is first up and we will look at his first air. Jordy is third surfer up and we will look at his "Superman" air when his feet come off the board.
To compare these two aerial moves we will measure height above the top of the wave at the peak for the air. We will do this because the camera footage allows us to see both the surfer and top of the wave in the same image for both surfers.
To measure their height above the wave we have to make some assumptions. Firstly we need to estimate the length of their surfboards. We will use this length to scale the video and allow us to measure height. We will assume that the board Dane was riding was 6 foot 1 inch (73 inches) Al Merrick Proton that he refers to in this video. We will assume that Jordy is riding a 6 foot 2 inch (74 inches)board as he talks about here.
Take a look at the images below. First Dane and then Jordy.
To compare their aerial heights we measured the height of their hips above the wave. Dane and Jordy both get their hips just under 5 foot (60 inches) above the top of the wave. Dane may be a little higher, an inch or so, but as the video of these aerial moves was taken from different positions and with different fields of view, we need to allow for some error. So we will have to say that both got about the same height above the wave.
So who did better? The judges scored Dane's wave with this aerial in round 3 of the event as a 9.33 out of 10 and Jordy's wave with his "Superman" air, also in round 3, as a 9.60. A wave is not judge only on one move though(unless its the only move) and Jordy did bigger moves on the rest of his wave than Dane. So maybe height of an aerial move does factor into the judges scoring and in this case the judges scored both waves high because of the incredible amplitude that both surfers reach.
Of course surfing is not only about being in the air above the waves but also about the movement, flow, power and combinations on the face of the wave. The 2010 Hurley Pro at Trestles was not won by either Dane or Jordy, but rather by the master of surfing, Kelly Slater.
Kelly is currently leading the World Championship Tour ratings going for his 10th title, but Jordy and Dane (2nd and 4th respectively) are right in it to. We expect the surfing will continue to be as exciting as it was at Trestles with these three athletes pushing each other to greater heights and hope to be seeing and analyzing the first aerial move 6 foot above the wave.
The world best surfer, Kelly Slater, whips around and starts paddling hard into a double overhead wave at Pipeline on the north shore of Oahu, Hawaii. His arms stroke deep into the water right next to the side of his board as he produces the speed needed to catch the fast moving wave beneath him. With another look at some video we also notice that he is kicking hard with his legs.
Getting up to speed
To catch a wave, a surfer needs to paddle the board fast enough to create the forward momentum that will ensure the wave carries the board and rider along with it and does not leave the surfer behind. The surfer must overcome the forces of inertia and gravity and match the speed of the wave as closely as possible. Large waves travel faster and therefore the board speed needs to be faster to catch these waves than to catch smaller waves.
A surfer increases his paddling speed by taking deep paddling strokes with arms close to the board and fingers together. This seems intuitive, but what about kicking hard? Does it really help to kick hard when paddling into a wave?
Slater kicks
In this video of Slater at the 2008 Pipeline Masters, watch how he paddles and kicks for every wave. From this video it is obvious that Slater kicks his legs when paddling into a large wave.
Why do surfers kick?
Kicking while paddling a surfboard has been carried over from freestyle swimming. A freestyle swimmer kicks:
To keep their bodies and legs floating high up in the water. This ensures the body maintains a straight line in the water, reducing drag.
To assist with body rotation and breathing. Breathing in freestyle swimming is timed with the kick.
Swimmers are taught to kick from the hips with slightly bent knees and an extended foot. Kicking from the hips produces the power which can translate into extra speed.
To increase swimming speed. Swimmers use a higher kick count to speed up in the water.
This may work for a freestyle swimmer, but a surfer may not get all the benefits listed above.
A surfer is lying on his board and is being kept afloat by the board itself, therefore kicking is not needed to stay afloat or to support the hips and legs.
Once again as the surfer is on his board with his head and chest up, he does not need to use a kick for breathing and he will certainly not want to rotate his body too much as that may destabilize him on the board.
On almost any surfboard that can be stood up on, the surfers hips will be pinned to the board while paddling and only his feet and knees will be in the water (depending on the length of the board). It is very difficult to kick from the hips while paddling a surfboard and therefore difficult to create the same kicking power as a freestyle swimmer.
Therefore the only advantage to kicking while paddling a surfboard may be to increase paddling speed.
The study looked at eleven young competitive male surfers and tested them in a field test in a 25m pool. The participants were asked to paddle as hard as they could for 10 seconds. Their paddling speed was measured with a tether like device which was connected to their waste and pulled a cable attached to a spool. The spool contained holes 1cm apart and an infrared light measuring sensor recorded the speed at each interval that the light could pass through the holes. The faster the spool spins the faster the surfer is paddling.
Over this 10 second interval the surfers averaged 1.73 meters per second when paddling with arms alone and 1.89 meters per second when paddling with their arms and kicking hard too. A 9.2% improvement.
So kicking increases paddling speed and Kelly Slater kicks so it must be good.
Surfers don't paddle into a wave for 10 seconds.
If you surf you will know that most of the paddling you do is out to the line up or to get into position for a wave. The sudden burst of paddling to actually catch the wave is likely to last at most 2 or 3 seconds.
From the Griffith University study we can see that kicking while paddling adds speed and allows the surfer to cover more distance (0.8m-1.6m) over a 5 or 10 second period. This will definitely help a surfer get into position for a wave or win a paddle battle for priority during a surfing competition, but does it help a surfer when paddling to match the speed of a wave?
If we go back and analyze the video above we can see that Slater paddles and kicks to get into each of his waves for at most 2 seconds. Theses first 2 seconds of paddling from a resting position are used to get up to maximum paddling speed (this can be seen in the Griffith University study graph on page 54) and therefore the surfer does not get the same 9.2% benefit that he would get over a prolonged 10 second paddle. The advantage will be less and will depend on how much more acceleration can be gained by kicking.
The average advantage of kicking over a 10 second period therefore cannot be used as proof that kicking while paddling will help a surfer catch a fast moving wave.
To kick or not to kick
Unfortunately the Griffith University study does not compare the acceleration that can be gained by kicking while paddling but we can assume that there is an advantage here. Even if it takes the same amount of time, say 2 seconds, to reach maximum paddling speed with kicking and without, the fact that the maximum paddling speed with kicking is higher suggests that the acceleration with kicking will be greater. In other words a surfer kicking will get to a higher paddling speed in the same amount of time than a surfer that uses his arms only. And a higher paddling speed is better for catching larger waves.
The study and physics suggest that if a surfer can kick hard while paddling he will gain an advantage however small it may be. Of course if the kicking destabilizes the surfer on the board or disturbs their arm paddling rhythm then it may in fact reduce paddling speed and make it hard to catch the wave.
The size of the board is also a relevant factor in deciding whether to kick. A good kick can only be maintained on a shorter board where the surfers knees are in the water and not on top of the board. The surfer is already restricted in kicking from his hips as they lie on the board, if the board was also under his knees he would be forced to kick the surface of the water and create turbulence behind him rather than using his feet as paddles just beneath the surface of the water.
If you are a surfer and have a video camera, get into a pool with your surfboard and line up your camera on the side of the pool. Do not push off the pool wall, but paddle straight from a still start for a measured distance say 10 feet or 5 meters, using your arms only and then using your arms and kicking too. Measure and compare the time it took to cover the distance and the speed attained at the end of the distance using a basic video analysis software and see whether kicking to catch a wave would work for you. Let us know what you find out.
The Surfing World Championship tour is currently in the middle of the second event of the season held at Bell's beach (made famous in the movie Point Break)and by now many surfing fans will know that the judging criteria for 2010 have changed.
If you are a surfer or simply a fan of competitive surfing and the likes of Kelly Slater or Mick Fanning then you will know that the Surfing World Champion is determined by the overall points winner of a 10 event world championship tour.
Each wave in a man on man competition in surfing is scored as the total of points for 2 waves. Each wave is scored out of a maximum of 10 points. Judges now reward progressive and aerial maneuvers with more points. So one extremely progressive, difficult move can potentially score a surfer 10 points if he performs it perfectly, lands it and rides out. Surfing judges use the following criteria to determine the surfer's wave score:
Commitment and degree of difficulty
Innovative and progressive manoeuvres
Combination of major manoeuvres
Variety of manoeuvres
Speed, power and flow
The new judging system obviously wants to see surfers try different and risky tricks and combinations of tricks and will reward them for landing these tricks. Although from our casual observance it seems surfers get some points for trying progressive maneuvers, they definitely get many more points when they punctuate the trick by landing it and flowing back into another move or back into the wave itself.
The video below has some excellent examples of progressive aerial surfing, at Bondi Beach in Sydney, Australia, by some of the Worlds best surfers.
The importance in the judging criteria of landing moves such as those seen in the video, means that surfers will need to spend time working on their technique.
With the help of video analysis they can assess their aerial maneuver take off positions, the height they attain and other factors during flight such as rotation. Landing positions that will allow the surfer to ride out of the maneuver and into the next one, require excellent balance and technique. All these factors which will lead to progressive moves can and should be analyzed.
The analysis can then help them to add height or variety to their moves, impressing the judges further and blowing the competition away.
Most pro surfers have hours of video footage of themselves to analyze. However many of these are shot for cinematic effect and may not give the best angle for analysis. With the new criteria pro surfers will also want to get video that will give them the best analysis possible.
For the rest of us, watching video of pros and capturing video of ourselves for analysis will allow us to improve our technique and general surfing. Please browse our site for suggestions on cameras and how to get great footage to do just this and contact us to let us know how you are getting on.
Sometimes it is simply fun to see a pro athlete perform in slow motion. Usually though we can learn a lot from watching him or her in such detail.
Surfing is one of those sports that lends itself well to photographs and video clips. The action is usually intense and the surfers positions so contorted that it is a wonder to see them perform. Of course because their movements are often quick and dynamic, it is difficult to analyze their motion at normal speed. Recently there have been attempts to analyze professional surfing from a scientific stand point of physiology and biomechanics. Check out a previous article we wrote about a trip to the Mentawai islands.
Recently the Quicksilver surfing team was in Mexico and took along a high speed vision research camera. This super slow motion camera can record at high resolution up to a frame rate of 7530 frames per second. We do not know the frame rate used to record this video clip, it is most likely at around 1000 fps. This does not sound like a lot when we consider that golf swings seen with the Swing Vision system are often recorded at 10X this frame rate. However it is generally accepted that the fastest movement that a human can make can be recorded at 250 fps, therefore a high speed capture at 1000 fps is 4X the fastest movement that the surfer can make. The reason Swing Vision uses a higher frame rate for golf is to capture the golf club and ball, which can move much faster than any part of the human body.
The video shows Dane Reynolds performing an aerial surfing move in Mexico, recorded by the Vision Research Camera.
Analyzing Dane's performance to learn how we can perform a similar move is easier because of the high speed footage. Lets take a look at some critical points.
Dane starts by balancing his center of mass (the center of all the masses and positions of all his limbs) between his feet, which are toward the back of the board. We can see that his weight is at the back of the board by noticing how the nose of the board is sticking up out of the water. We also see him leaning into the face of the wave so that he can turn quickly to launch into his aerial move.
Mid way up the face of the wave, Dane applies more pressure to his back foot, shifting his center of mass further back. We see his front knee straighten and his head lift up eyeing his take off point. The movement prepares him to almost jump off the wave with his back foot when he reaches the top.
At take off Dane pushes his back foot almost straight (jumping). He does this to launch the board into the air and also to bring it up closer to his hands so that he can grab it.
Once in the air, just off the wave we can see how Dane pushes the board around with his back foot, while bending his front knee. He also lifts his head up and forward as if he is trying to peer over the top of his board. This enables him to get the rotation needed to bring his body on top of his board so that he can set up for the landing. In fact it almost looks like he is climbing up his floating board with his hand.
Now that he is in the air and has got back on top of the board he needs to prepare for the landing. This time, unlike when he was riding the wave at the beginning, he positions his center of mass over the middle of the board. This will give him a bigger landing area. If he positioned himself over the back of the board as he did at the start, the board would most likely slip forward and out from under him on landing.
On landing he stretches out his legs to reach for the top of the wave and then allows them to bend to absorb the landing impact. Notice how his arms are in an equal and opposite balancing position over the center of his board to keep his weight centered.
Interestingly on his landing we can see the flex or wobble of the board itself, which probably gives him a little more shock absorption.
Finally riding out we can see that Dane's body is leaning backward a little and the board is sliding out forward. This is probably a result of his not having his center of mass directly over the center of the board at landing. However Dane quickly recovers by bending his knees and moving his arms forward to once again position himself over the center of the board and ride out.
Breaking down a movement using high speed video footage can be very instructive. If you are a surfer, we hope you were able to pick up a few tips. If you are not a surfer, take a look around for high speed video footage of your sports and see what you can learn from the pros. If you have any suggestions of high speed video you would like us to analyze let us know. We enjoy hearing your comments.
Anyone who has seen a surfer or skateboarder pull off a flying aerial move is amazed that a human can do such an incredible trick. Although we are all completely dumbstruck by the performance of these maneuvers, these sports often have an unfair reputation of not being truly professional. We often consider these athletes to simply be kids who have spent too much time playing around on the beach.
Surfing and Skateboarding are no longer sports dominated by athletes with talent only. These professional athletes spend many hours training. Professional surfers now spend almost as much time out of the surf, working out (often with trainers) on balance balls, with weights, and in the gym and swimming pool. They do thorough warm up sessions before going out to compete and often also have cool down routines for after a surf.
The use of scientific analysis in surfing has been long in coming. There are a number of reasons for this and I won't give you a history of soul surfing, but the main reason is the difficulty of doing any physiological or biomechanics testing on a surfer. Because surfers do their sport in water and shifting, changing waves (size, direction, steepness...), it is very difficult to test them in the same conditions and obtain relevant scientific results.
Recently, for the first time a team of scientists joined some professional surfers in the Mentawais and recorded their paddle speed, surfing speed and heart-rate during surfing sessions. They also took blood samples to monitor lactic acid build-up and hydration data. These scientists were able to provide the surfers with some physiological and performance data which will surely help them to train better for competition.
Using video to analyze surfing is another way in which these athletes and other non-professional surfers could improve their performance. The professional surfers get lots of video of their performances from all different angles and we hope they use this information to make improvements. Of course, because of the changing waves and the 3 dimensional nature of surfing (moving up and down, forward and sideways), it is difficult to make comparisons with video.
As we looked through some of the video from the surfing trip to the Mentawais, we found one of Jordy Smith of South Africa, performing a Rodeo Clown Flip. We won't try to describe the move here. At about the same time at a competition in the Maldives, an American surfer, Patrick Gudauskus was completeing the first ever rodeo clown in competition. We have decided to look at both these videos and compare their performances. Jordy's wave is the first video and then Pat's wave is the first part of the second video.
Once you get over being completely amazed that surfers can do such things on a wave, take a closer look.
The first thing you will notice is that Jordy is on a much bigger wave than Pat and this can make comparison difficult. We can still look at the technique though and we will do this in stages.
The Setup: Jordy launches into his rodeo clown with his board facing almost vertically up at the sky, while Pat's board is about 30 degrees from the vertical when he launches. This may be because of the size of the wave. However, what is obvious is how this affects the height of the flip. Jordy's vertical entry helps project him higher into the air.
The Take Off: Here both Jordy and Pat transfer their weight onto their back foot. This helps them launch the board out of the water, bring the board up to their hands for the grab and creates the rotation by pushing on the back of the board.
The Grab and Spin: Once again they both use a similar technique here. They both grab the board quickly once they are in the air and begin their rotation. Some of their rotation has come from the back foot pushing on the board but once they are in the air they both use their heads to complete the spin. Watch how they both turn their heads to their left (the direction of spin) . If they did not use their heads to turn they would not be able to complete the spin.
The Top of the Flip: As they spin around both surfers actually travel upward to their high point. The high point of the flip is determined by the surfers maximum height above the wave. It is obvious here that Jordy is much higher than Pat throughout the flip. At the top, Jordy's body and board are well above the wave (we can see sky and clouds between him and the wave). Pat's board and body are at just about the height of the wave. Although in this case it does look like Jordy is much higher we need to clarify this by pointing out that Jordy is on a bigger wave (this is not controlled by the surfer) and the camera angle filming these two flips is not the same and therefore the camera angle used to film Jordy's flip may be making it look much higher than it was.
The Landing: The landing of course is dependent on all the other factors that occurred before, including the take off, spin and height. Jordy has rotated further and is still above the wave as he prepares to land. He therefore needs to stretch out his legs to find his landing and ride out of it. Pat, on the other hand has not been able to rotate as far, because he did not get the same height above the wave. He is forced to land low down, but by landing with knees bent and hands still on the board he too is able to ride out.
So both of these flips were spectacular and although they looked different they were actually performed with similar techniques and there is a lot to learn by analyzing the videos.
Unfortunately, those of us who surf for fun and do not have sponsors, do not have too many opportunities to see ourselves in action. You can however set up a camera on a beach or get someone to film you from the beach. Try to get video looking straight out at the wave from the beach. It is difficult to analyze your performance when studying video that was filmed at an angle to the wave. It is also useful to have some sort of calibration scale that can be used to measure height (as we did in a previous post on Measuring Jump Height). Of course if you can get more than one camera setup you can really take a look at your technique from multiple views, which makes sense for a sport such as surfing.
We love to hear your comments or suggestions. Let us know what you think or what you want to see posted.
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