Baseball purists have successfully delayed the use of video replay technology for a very long time. Arguing that the tradition of making all calls visually by the field umpires is the only way to go, a seemingly increasing number of blown calls have pressured the MLB to begin adopting video replay to help minimize inherent human errors.
In 2008, the MLB begin using video reply for the following calls:
Home run calls (fair or foul)
Whether the ball actually left the playing field
Whether the ball was subject to spectator interference
This obviously doesn't cover every single call, but there is a point of diminishing return on the use of replay. However, there are still some more calls that we think warrant the use of the technology. On June 2, 2010, Armando Galarraga pitched what should have been called a perfect game for the Detroit Tigers. However, on what appeared to be the last out, the umpire called the runner safe at first base. Even the runner and his teammates thought the game was over. Replays from every available angle clearly show the defensive player had his foot on first base and the ball in his glove well before the runner reached the base. So instead of having the third perfect game thrown in 2010 (and only the 21st EVER), Galarraga continued to pitch until the final out was made.
As you may well know, baseball fans are obsessed with statistics and records. So we'd have to believe even the most traditional fans think it's a shame that such a brilliant performance be left from the record books due to a blown call. Certain calls are meant to be subjective, such as strikes and balls; and it's an enjoyable part of the game to watch how the players must make minor adjustments based on who's behind the plate that day. But other calls should be black and white (i.e., a player either reaches a base safely, or is out), and these are the types of calls that should subject to video replay.
On a somewhat unrelated note, Galarraga handled the situation like a champ. He just grinned at the bad call, and went right back to work, pitching the remainder of a shutout. Many other players would've acted like a two year old and thrown a tantrum; many others would've lost the mental focus required to perform at a high level. So hats off to you, Armando - not only for a terrific pitching performance, but for simply respecting an umpire's (incorrect) call, and showing some real class.
Throughout his high school playing career Jason Heyward was always recognized as a prodigious baseball hitting talent. This recognition and the hype that began early in 2010 with his debut in the Major Leagues have proved to be legitimate.
Heyward has lived up to his reputation. He began his professional career by hitting a 3 run, home run on the first at bat of his MLS career for the Atlanta Braves against the Chicago Cubs. He has followed that first strike up with 7 more home runs and a batting average of .276 for the season.
Heyward has started his MLS career this way because throughout his youth league and high school playing career, he has practised perfect hitting mechanics.Below is some video of Heyward hitting at different stages as he advanced in the youth leagues, 2004, 2005 and 2006.
From the video we can see that Heyward from as early as 2004, has been taught and understood how to create power in his hitting by using his large body parts such as the hips, torso and shoulder and combining this with perfect timing.
On this site we call that the Kinematic Sequence. The kinematic sequence can be described in almost any hitting or throwing sport. By rotating the major body parts in sequence the hitter is able to create bat speed. The hitter starts in the wind up position, bat above the head shoulders and hips rotated away from the pitcher. He then begins the kinematic sequence by planting his front foot and unwinding in sequence, first the hips, followed by the torso and shoulders, then arms and finally the bat.
Each subsequent body part rotates quicker than the previous one until in the end the bat has accumulated all the speed from the sequence and can strike the ball with power created from the movement of the whole body and not just the arms, wrists and hands.
Lets break down Jason Hayward's swing and take a look at his mechanics and kinematic sequence.
These first 3 pics show Heyward at the load position in 2004, 2005 and 2006 (left to right). Notice how as he gets bigger and stronger he continues to maintain that loaded position of shoulder and hips facing away from the pitcher. This stance prepares his body like a compressed spring to release all the energy necessary.
As he moves through his swing we see that Heyward takes a step forward and drives with his hips first rotating them to face the pitcher while his shoulders, arms and bat remain behind. His shoulders and arms are beginning to rotate at this stage. By rotating his hips first he is using their rotational speed to increase the speed of his shoulder rotation which will follow.
Just before ball contact Heyward has now rotated his hips and his shoulders and now only the arms and bat need to hit maximum rotation speed. Each large body part has built on the speed of the previous one and thereby increased his bat speed. To get maximum speed he still needs to complete the swing by following through. His bent arms allow him to hit through the ball and follow through to maintain balance and control.
As we look through the video and the images, we notice that Heyward practiced perfect mechanics from as early as 2004 and probably before. His batting coaches made sure he used proper technique throughout his career. From 2004 to 2005 and 2006 and on to his MLB career he has continued to put together his swing using the kinematic sequence of events.
Of course there are other factors in Heywards past and possible future success. His size and strength (6'5", 240lb) are definite bonuses. However a powerful hitter will need to use all his most powerful muscles to have a long and successful and injury free career. In fact Heyward currently has a small groin strain but this is more likely the result of stretching for an outfield play rather than anything to do with his hitting. We hope to see Heyward continue to impress and as long as he maintains the perfectly practised mechanics we expect he will.
Practising perfect mechanics is an important element of training for any sport. It is very difficult for a good young athlete to change his bad habits after practising them for many years. Video analysis can help to pick out these bad habits and correct them at an early stage allowing your athletes and kids to practice good mechanics, avoid injuries and improve faster.
More blown calls in a major sporting event. This time in the 2nd game of the Major League Baseball World Series, between the New York Yankees and the Philadelphia Phillies. Chase Utley of the Phillies was called out at first base, when video evidence suggested he had touched the base before the ball hit Mark Teixeira’s glove. In the same game Ryan Howard was judged to have caught out Johnny Damon, when the ball looked to bounce before hitting his glove. There have been a number of poor calls in this seasons MLB playoffs once again, and blown calls are happening in numerous other sports, including soccer and tennis.
The technology of high definition and high speed video of today can easily eliminate many of these blown calls. Sure there is the argument that using video replay can slow down the game. In baseball in particular this would be truly frustrating, but we would I think all prefer to see the right call made most of the time, particularly in big games such as the World Series.
Cricket is a great example of where camera technology is used to good effect. The cameras are setup side on to the crease (batters line) and can see both the wickets and the crease. In most cases just this one camera would be enough to determine the position of the batter as well as whether the wickets bails had been dislodged. If the umpire on the field is unsure of a run out situation, he will refer the decision to the camera technology, or the 3rd umpire, who will make a definitive decision after reviewing the video footage.
Although we definitely support the use of video analysis to assist umpires and referees, it is important that everyone; umpires, athletes and fans understand that even with video analysis a call can not be 100% correct every time. Video footage cannot always capture the event from the correct angle or the video cannot be slowed down sufficiently to determine some calls. The fact is that the video footage may not show enough evidence to support or over rule a call.
Fans in particular make the mistake of believing that video evidence will always be able to determine whether a call is correct. Unfortunately this is not the case. If the camera reviewing a line call or judgement does not have a direct view, then the video image may not help to determine the accuracy of the umpire's call. When close calls are viewed from an angle given by a television camera, they can sometimes give misleading evidence of the accuracy of the call. This can be particularly problematic for example, when using one camera angle to determine whether a base runner has been thrown out. The base runner is running between the bases and the camera could be setup at a good angle to view when the runner touches the base. However, and here is the problem, the ball may be thrown in to the fielder from anywhere on the field (this cannot be determined in advance), therefore the camera setup to view the runner may not be in the best position to accurately determine when the fielder caught the ball and it will be possible for incorrect judgements to be made. If on the other hand we have a great view of the fielders glove and ball, we may have the incorrect perspective of the base runner and when he touches the base.
Of course these 2 situations did not take place in the 2nd game of the MLB World Series, but they also cannot be discounted.
Take a look at the 2 photographs below.
In the above pic we have the view from one camera and shoe looks like it is on the edge of the mat. Now lets take a look from a second camera with a better view of the edge of the mat and the shoe. Of course it is pretty obvious from this camera angle that the shoe is just short of touching the mat. From this we can see that the incorrect camera angle could result in an incorrect call.
The problem of incorrect camera angle could be solved by having multiple cameras, all synchronized with a time source and calibrated so that the 3D position of the ball can be determined. This is how the Hawk-Eye system for Cricket and the Tennis challenge system works. Beside the fact that this type of technology requires numerous cameras, can be very expensive and requires processing time before a decision can be made, it too can suffer from inaccuracies when the ball or target being tracked is hidden from the view of a number of cameras. This can often be the case when their are numerous players on the field, or the lighting is not ideal.
So we know that video analysis of umpiring and refereeing decisions are not 100% accurate. In fact the Hawk-Eye system claims they have an accuracy of 3.6mm. This means that the ball can miss the line by 3.6mm in Tennis and still be called in by the system. In NFL football when a call is challenged and a review takes place, often the result suggests that there is insufficient evidence and the call on the field cannot be over ruled. This insufficient evidence occurs because the camera cannot get the best view of the ball and its position because of the scrum of players or a camera angle that is not optimal.
The umpire or referee has a distinct disadvantage to technology. He or she only gets one chance to get it right. If they fail to get into the best position, have the best view of the play, find the best perspective to catch all the action and happen to blink at the critical point, they could easily make the wrong call. The camera even with the possible errors in perspective or lighting and the small errors with 3D tracking , can capture high resolution and high speed footage and replay it over and over again. This advantage will ensure that technology will get the call right more often than even the best and luckiest umpires and referees and should be used whenever an umpire is unsure of the call to be made.
A final thought. While we wait for technology to be used, we should remember that even video footage could result in incorrect decisions. There will always be some statistical error, only a lessor error than those made by human umpires. Fortunately with technology, line calls can not be biased by emotion but only based on whatever video footage is available. With this technology even the teams we support will catch a few breaks in the long run.
The Major League Baseball post season is nearing an end. The League Championship series are in full swing with two great match ups. The Los Angeles Dodgers are taking on the Philadelphia Phillies and the Los Angeles Angels have the formidable task of attempting to overcome the New York Yankees.
Baseball particularly in the post season is dominated by the pitching. Great batters are successful only around 30% of the times they come up to bat but great pitchers on the other hand can dominate and beat the batter 80% of the time. A great pitcher needs to be able to throw a variety of balls, so that he can beat any batter and can throw to the batters weakness.
There are 3 pitch varieties, the fastball, breaking ball (slider or curve ball) and the change up.
The pitcher must then be able to throw each of the 3 pitches listed above to hit 4 different targets: high inside and outside and low inside and outside.
The pitcher also needs to understand the batter he is up against, his strengths and weaknesses. Is he left or right handed? Does he have an open or closed batting stance?What did the batter do on his previous at bat?
Finally the pitcher also needs to throw pitches according to the pitch count. This is often called pitch strategy. The pitch strategy will change as the number of strikes and or balls change. For a detailed description of pitch strategy have a look at this article by Tom House.
In the first game of the American League Championship final between the Angels and Yankees , we watched CC Sabathia of the Yankees put in an excellent display of pitching. He pitched to all corners of the plate and varied his pitches with the pitch count and player.
Below is some video of Sabathia pitching strikes to the Oakland A's in August this year. Watch for the variety of his pitches, fastballs, breaking balls and change ups, as well as the numerous targets he hits, inside and outside, high and low, to both right and left handed batters.
Sabathia is one of the best in the MLB this year and his ability to pitch a variety of pitches is one of the main reasons for this.
However it is also important when throwing these different pitches that the player is able to disguise the type of pitch he is going to throw. If the pitch is well disguised it gives the batter less time to react to the pitch and reduces their chances of getting a hit.
Lets look at the video of Sabathia again. Notice that his action is always the same for every pitch, whether it is a fastball or a slider, whether he throws high or low. Focus on Sabathia only as you watch the video.
Sabathia covers the ball with his glove at the start of every pitch.
He rotates his shoulders back the same amount each time. He also lifts his front knee to the same height on every pitch.
He seems to stride forward to almost the same position on each pitch.
His arm comes through at the same speed and height for all his pitches. Most of the pitches he throws in the video above are in the 83-84 mph range, but the 2 faster pitches 88 and 97 mph look very similar to the others.
His follow through for all pitches also looks the same. His head remains looking up and forward.
He even completes the routine after the pitch in the same way by pulling up his shirt sleeve.
We all know from our experience that the video above is not the best for analyzing Sabathia's technique or timing. The best footage would be from the batters perspective, but from the angle we have, it certainly looks like each pitch is very similar. If the batter is able to read the pitchers mechanics and guess at the pitch to be thrown, he will have that little bit more time to modify his swing and get a hit. By throwing different pitches using the same technique and timing, Sabathia is able to delay the batters decision to swing and therefore is able to beat them more often.
The best technique for throwing all types of pitches is the same, there should be no need to vary your technique to throw a different type of pitch. To throw a curve ball, slider or any other type of pitch the variation is in the grip and in the final position and snap of the wrist, not the pitching mechanics.
To pitch like CC Sabathia, concentrate on the pitching mechanics. Fool the batter by showing him or her the same mechanics on every pitch. We will follow up with a video analysis of good pitching mechanics soon. In the mean time enjoy the post season and World Series. Keep an eye out for Sabathia and see if you can spot any variations in his mechanics with each pitch.
Batting in cricket is altogether different from batting in baseball in both objective and technique as well as the bat itself. In cricket the batter can hit or play at and miss as many of the balls bowled as he or she wants with a flat faced bat and scores by running between wickets or hitting the ball over the boundary. In baseball, it is 3 strikes and you are out and home runs or base hits, hit with a rounded bat, are the goal.
In both sport, professional bowlers or pitchers can deliver the ball at around 100 miles per hour and therefore timing and reaction are very important. In cricket though the batter can play a shot anywhere on the oval field, even behind him as long as he does not get caught or run out (I will not go into the rules of cricket but you can find them here). This means that in cricket there are a large variety of shots that can be played that require exceptional timing as well as perfect technique.
One of the classic and most eye catching shots in cricket is the straight drive. Most of the best cricket batters in the world such as Jacques Kallis and Ricky Ponting play this shot with ease and little effort.
Here is some video of Sachin Tendulkar, another cricket batting legend playing some straight drives off one of the fastest bowlers around, Brett Lee. The first shot is slightly mistimed and the ball angles off his bat, but the next 2 shots are perfect examples of a straight drive.
His timing and technique in the second shot is perfect and therefore requires little effort to transfer power and speed to the ball so that it races along the ground to the boundary and 4 more runs.
Let's analyze the video and break down his technique:
Tendulkar starts his movement by stepping with his front foot toward where the ball will bounce on the pitch and lifting his bat. As the ball is coming toward him at around 145 km/hr, he has very little time to react and therefore must move toward the ball and plan the shot he will play at the same time.
As bowling in cricket requires the ball to bounce, it can change direction and speed quite a bit after the bounce. Stepping forward to the area in which the ball will bounce allows the batter to get closer to the bounce and reduce the amount of movement that can occur after the bounce. This also allows the batter to get over the ball and prevent the shot from flying through the air and giving one of the fielders a chance to catch it.
Tendulkar brings his bat down straight with the flat face of the bat directed at the ball. Angling the bat will force the ball off in the direction toward which the bat is angled and also increases the chances of catching the edge of the bat or missing the ball completely. Although batters do sometimes play shots by changing the angle of the bat, you will not play a good straight drive with an angled bat.
Tendulkar connects with the ball around 1:21. By pausing the video you will see that his bat is alongside his front leg at the point of contact. His weight is also forward and over the front leg. He does this so that he can hit the ball directly toward the ground giving no chance for a catch. This timing also ensures that he has perfect balance and control over the shot.
He keeps his head down looking at the ball being hit off his bat and continues to keep his head down as he begins his follow through. Just as in other sports (golf, rugby place kicking) this helps him to maintain his balance through the shot and once again to keep the ball from lifting into the air.
Tendulkar then continues to follow through keeping the flat part of the bat facing in the direction he hit the ball and bringing his arms all the way above his head. This ensures that he hits straight and all the way through the ball.
The results of this perfect timing and technique are obvious as the ball flies off to the boundary and 4 more runs for Tendulkar.
The 2009 ICC Champions Trophy begins September 22 and the likes of Jacques Kallis and Ricky Ponting and Sachin Tendulkar will be showing off their batting prowess and often flawless technique from which we can learn.
The only way to win in Baseball is to get some hits. Looking at the statistics of Major League Baseball, where most of the best players and hitters in the world play, we can see that hitting is more difficult than it looks. Babe Ruth for example had a career hitting average of .342, while this 2009 season Albert Pujols leads the MLB on hitting average of .333.
This means that Babe Ruth only hit a base hit or home run 34.2% of the times he was up for bat, while the best hitter in the MLB this season, Pujols has only hit 33.3% of the times he has been at bat. These hitting averages for the best players seem low, but we should also consider the challenges of hitting a baseball pitch and understand that hitting averages over 30% are in truth very good.
Here are some of the challenges:
The pitcher can throw a fast ball, slider, curve ball and many other variation. The hitter needs to read the pitch correctly to get a good hit.
As a strike will only be called if the ball is pitched in the strike zone, this is the best zone to swing the bat through. However the pitcher can try to fool the batter by pitching a ball that looks like it will go through the strike zone but then fades away or drops out of the zone.
Once the batter is able to make contact with the ball, he still needs to find a gap in the outfield so that he can run to first base and score his hit. This requires timing and control to get the ball into the gap.
Of course the ultimate is to hit a home run. This requires timing and power to hit the ball far enough and high enough to clear the outfielders and the fence.
Improving hitting mechanics can help a player improve his hitting average. Here we will take a look at some video of a young hitter at practice and discuss some of the important aspects of hitting.
Our hitter here is practising by hitting balls that are tossed up to him and therefore may not be falling in the strike zone but we can still examine his hitting technique.
The video camera in this instance has been set up so that we get a side on view of the hitter, this allows us to examine his stance, hips and shoulder rotation as well as take a look at his bat swing plane. Another aspect of this video that we like is that it is high definition. Unfortunately because the capture rate was around 30 frames per second it can be difficult to see the bat swinging through to track the swing plane but we have made our best effort to track this.
Taking a look at the swing itself, we can break it down as follows.
Our hitter loads up on energy for his swing by rocking back onto his back foot. This allows him to get ready to swing his bat at the ball.
He steps forward a little with his front foot. He does this to get good position on the pitch (or in this case toss) and to open up his stance and allow his hips to rotate through.
He rotates his hips and shoulders through to make contact with the ball.
Steps 1 and 2 in this case look good. Our hitter has setup well to hit, and he has moved his front leg toward the ball to open up his stance to get a good hit.
In order to create power though, we want to remind you about the kinematic sequence. We discussed the kinematic sequence when we talked about Tiger Woods' golf swing. The kinematic sequence is the sequence of events that creates the bat speed. To create good bat speed the hitter needs to rotate his hips, shoulders, hands and bat in that order, with each following segment moving faster than the previous segment.
Here is how it works. The hitter loads up to hit as can be seen in step 1. He then steps forward to open his stance. His hips now need to rotate through toward the ball, but his shoulders should remain behind. By rotating his hips and leaving his shoulders behind he creates potential energy. The shoulders then follow the hips, as the hands and bat are now left slightly behind and with potential energy. Finally with perfect timing the hands follow and then the bat, to hit the ball in the strike zone and with power and control.
In golf, the ball is not moving and so it is easier to practice the kinematic sequence. In baseball hitting the ball can be pitched with much variation and it can be much harder to get this timing correct. However in baseball we once again have a smallish strike zone as well as a a hitting angle of only 90 degrees (between 1st and 4th base), therefore the kinematic sequence must be employed in the same way.
We took some snap shots of our hitter at key moments to examine his hip and shoulder rotation more closely.In the first image we can see our player setup correctly. His weight has been moved to the back foot and his bat is nicely positioned
His pelvis alignment can be seen with the blue line, while his shoulder alignment is represented by the red line. At this point, prior to loading and before the actual swing starts, his pelvis and shoulders are aligned.
In this second image, we can see that our player has now rotated through and is ready to make contact with the ball. In this case we can see that his hips (blue line), shoulders (red line) and bat (white dot on yellow trajectory) are all already lined up. The timing of his kinematic sequence is a little too fast, his shoulders, hands and bat have caught up with his hips too early. To create optimal power, his shoulder rotation should be following his hips, his hands should be following his shoulders and his bat following his hands. The result of this mistiming is that our hitter will strike the ball early and with less power.
Our player though does swing through a nice arc with his bat (yellow trajectory). We can see that he keeps his arms extended through the swing. This allows him to increase his bat speed and follow through with the hit.
In a final thought, our player has a good swing. He loads up nicely, steps toward the pitch and swings his bat through well. His sequence timing may be a little too quick, but this may also be because the ball is being tossed up to him rather than pitched and he has to reach for it outside the strike zone.
Baseball hitting and pitching lends itself well to video analysis, because the athlete is standing in one spot and hitting or throwing. So get your cameras out and make sure to follow the rules for setting up to capture good video for analysis and you will be able to analyze your hitting or pitching in much the same way as we have done here.
We would like to thank Mike and Aaron Kocourek for this video.
Welcome to the Video Analysis of Sports blog. As this is our first article, we will take this opportunity to introduce ourselves.
We (Dennis and Dudley) have a combined 20 years experience in motion capture and biomechanics with a special interest in sports performance and injury prevention. Through our consulting company Sadaka, LLChttp://www.sadakallc.com ,we offer services to sports professionals, sports equipment manufacturers, hospitals and motion analysis software and hardware companies. Some of our past clients include Titleist, FootJoy, Warrior Hockey, National Pitching Association, NASA, ShrinersChildrens Hospital and Vicon Motion Systems.
Video analysis of sports performance is often the domain of professional athletes and large companies or research institutions. This analysis is done with expensive 3D video camera equipment and complicated software to ensure high speeds and accuracy. However there are some basic techniques that can be used by any individual to evaluate their own performance and get great results using a simple digital video camera and a little understanding of biomechanics. The video camera will require a small cost (we will discuss what makes a good camera in a future posting), but we will supply you with much of the biomechanics understanding for free on this blog.
Reviewing video clips can be a great way to provide coaching feedback to players, as well as a means to emulate one's favorite athletes. Whether you're a professional all-star, high school athlete, or weekend warrior, seeing yourself from a different perspective can help improve your performance and/or minimize your chances of injury.
So in this first posting, we'll start right at the beginning and describe what features make a sports clip suitable for video analysis of an individual, and what you can do to ensure the clips you film will meet those requirements. Future postings will demonstrate the various levels of analysis that can be performed on suitable videos, using a range of available software, from basic free software to detailed 3D analysis.
What makes a good sports clip? A good sports clip of an individual shows the athlete's full range of motion (ROM) during an action, with the camera positioned such that angles can be accurately calculated (this will be discussed in more detail later). Filming the athlete's ROM can be accomplished by simply zooming out or moving the camera backwards until all the desired features are in the viewer. In general, it's recommended to have the camera as close to the athlete as possible and still capture the entire ROM, as this will make the most use of the camera sensor's resolution. For example, if we were to capture a basketball player dunking the ball we would want to ensure that our camera can see the complete action from take off until the player puts the ball in the net. Our camera would therefore need to see the ground at the take off point as well as some space above the rim of the the net.
Another important factor in obtaining a great sports clip is to make sure that your camera is stationary. There are some motion capture software available that can handle a moving camera, but for now we suggest that the camera is mounted on a tripod and is not moved while the video clip is being filmed. This means that you should ensure the full ROM (described above) can be captured in this one shot.
How you can film useful footage: Camera placement In general, most sports clips we watch on tv are best suited for analyzing strategy and teamwork because they provide an overall picture of many or all of the competitors and the playing field. However, when it comes to analyzing an individual's performance or technique, it's not only important to focus the camera on the single athlete, but the angle we film from must also be taken into account. It's best to use "orthogonal angles", meaning the camera is directly in front of, behind, or to the side of the athlete. Golf coverage usually does a nice job of this, providing shots of the golfer either "face-on" or "down-the-line". Here's a great face-on view of Tiger Woods' swing:
And here is a down-the-line shot of his swing:
Notice these cameras are level with the golfer; they're not filmed at an upward or downward angle, meaning it's possible to accurately calculate some angles, if that's what is desired from the analysis.
Background/contrast Although the above clip is a beautiful view of Tiger's swing, the footage could have been improved by having him wear clothes that were a different color from the background. Black clothing with a black background can make it difficult to accurately evaluate the amount of hip and shoulder rotation - two commonly analyzed characteristics of a golf swing. Not that having a solid black background is a bad thing though; on the contrary, if you can manage to film your athlete with a solid-colored background, you are well on your way to filming some nice footage for analysis.
Lighting As is true with taking most photos, it's ideal to position the camera and athlete such that the light source (e.g., the sun) is behind the camera and illuminates the athlete. This will provide a crisp view of the athlete, and will allow you to use a more open setting on the camera's aperture.
Now that you're up to speed on the basics of filming great video for analysis, grab your video camera and start practicing! Follow our regular blog postings, and see how you can create your own analyses of your videos, using a variety of software packages.
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