Arm Action

The detailed discussion of optimal throwing mechanics is going to be segmented so that the arm actions and Legs and Torso actions are separated. In reality, the arm and body are tightly linked, but from a teaching perspective we want to be clear about the way the arm works and then how the rest of the body works. In addition, the discussion and teaching concepts will break the mechanics into the movements prior to and after the stride foot landing. The stride foot just prior to landing, as shown in the following picture of Paul, is the key throwing position because it is the point where the arm action should switch from the reverse (backward) arm swing to the arm whip.
It is important to emphasize that this site is intended to guide players in the establishment of an optimal arm position from which a powerful turn can be executed by the large muscles of the body to generate maximum arm speed.

The majority of young players that we have seen over the years have not had the desired arm position prior to foot strike. For most of the young players the arm action (and body action) can best be described as a blended technique that linearly develops and expends energy. This throwing method is compared to a hard thrower’s mechanics that achieves a defined arm position prior to foot strike, and from this position throwing energy is developed. A smooth, linear throwing action is even typical of many advanced players that I see in high school, in college and in the professional ranks. A smooth, even transition from the reverse arm action through the forward throwing action can be accurate and can prevent injury, but it cannot generate maximum velocity. Maximum velocity occurs when there is a violent, maximum effort turn that is executed, starting from the desired arm position just before foot strike.
You may be asking yourself, “why, if some professional players throw with a blended technique, is it so important that young players learn to throw with the techniques described on this site”? The answer is that major league players typically have exceptional, if not freak of nature, athletic ability and physical gifts. The fact that a six foot six, 240-pound major league pitcher can throw 90 plus miles per hour with a less than optimal set of mechanics doesn’t mean that a five foot eleven, 175-pound high school player will get anywhere close to that velocity using the same technique. The more average player with more average athletic ability must utilize every bit of leverage and technique available to him to get close to average major league arm speed.
So, the intent of this site is to break the mechanics down into the fewest number of steps that will allow the player to get into the ideal position prior to foot strike and then utilize the major muscles of the body to accelerate the arm to the maximum amount. After release of the baseball, proper technique is needed to allow the arm to decelerate through a long controlled finish. We will begin by working on the critical arm actions.
The Grip
One significant problem that reduces velocity for a lot of young players is the actual hand position on the baseball. For younger players the grip may be limited by the size of the hands, and for older players the grip may be caused by the player wanting, subconsciously, to be in control of the ball. I believe the problems arise at a young age, when the player needs to grip the ball tightly to hold it in his small hand. The typical poor grip consists of the ball tucked deep in the hand so that all of the joints of the middle and index fingers (even the ring finger) make solid contact. The incorrect grip for the thumb is with the soft pad, opposite the thumbnail, in full contact with the side of the ball as shown in this picture. Using this grip, the player feels like he has complete control of the ball, and he does.


One of the unfortunate results of this strong, controlling grip on the ball is a ball flight that isn’t true and straight to the target. Rather, the thrown ball has side spin and the flight of the ball tends to curve and sink. This lack of “carry” on the baseball is most obvious when you ask players to throw to you from the outfield. The increased throwing distance allows a coach more time to view the flight path of the ball and recognize issues. Typically, a young player’s grip pressure is quite high and this, coupled with the previous grip discussion, causes a weak ball flight.
Earlier in Throwing Problems we discussed my grandson Kolt’s elbow discomfort associated with throwing the baseball with “slider” spin. The grip shown in the picture above will tend to cause the “slider” spin to develop since the thumb is on the inside of the baseball and the fingers are on the outside at release rather than the fingers being on the inside. The term “inside” may be confusing, but it refers to the part of the hand that is “closest to the body”.
A proper grip isn’t the controlled grip pictured above. The proper grip needs to allow the maximum whip of the ball through relaxation of the arm and hand. As a coach, you need to evaluate your player’s hand size and determine how closely the player can come to achieving the optimal grip. In general, the younger the player the more difficult it will be to exactly implement the proper grip.
Another grip problem results when the player has a wide spread between his two fingers. Ideally, the first two fingers are just barely separated, but for a lot of players I have coached the fingers were separated by an inch or more. The result of the fingers being spread is a restriction in the hand and forearm which reduces hand speed. As an example, when Paul was throwing his split finger he separated his fingers by an inch or more and the result was a decrease in release velocity of 3-5 MPH and increased movement on the baseball.
The ideal grip for all players depends on a relaxed hand and wrist. The index and middle finger should make contact with the ball with light pressure applied primarily from the surface beyond the second knuckle. For young kids with small hands, the index, middle finger and ring finger may be required on top of the ball.  The thumb should be on the opposite side of the ball from the fingers at a point that is centered between the fingers (if the fingers are on top, the thumb is on the bottom.) The edge of the thumb should contact the ball, near the side of the thumbnail. There should be sufficient room between the ball and the palm of the hand to insert two fingers. Again, the age and physical size of the player may limit the ability to achieve this ideal. In the following picture, the described elements are clearly demonstrated. The ring finger touches the side of the ball and little finger is essentially off the ball.
This picture shows a “4-seam” grip which causes the baseball to spin almost purely backward after release with four seams cutting through the air on its forward path.


After a young player has thrown with a firm, controlling grip for several years, the optimal grip will feel very weak and uncomfortable. I generally ask the player to practice working with the ball without throwing, trying to make the correct grip feel more comfortable. Unfortunately, the player will generally resort to the old comfortable grip when he starts to throw. The ideal grip takes a lot of repetitions before there is a change in what feels natural. There is a grip drill on the site that should help if it is repeated many times.

A proper grip uses light pressure of two fingertips on top of the ball and the edge of the thumb on the bottom…

The optimal 4-seam throwing grip achieves the highest average velocity. For example, there may be as much as a 3 to 4 miles per hour increase in the average velocity of a pitch thrown approximately 90 mph using a four-seam grip compared to a pitch thrown using a two-seam grip (one type of two-seam grip is shown here). This is true even though the velocity of the ball coming immediately out of the hand at release can be the same for both grips (A Jugs gun measures the maximum velocity out of the hand and a Ray gun measures the average velocity from the hand to the plate.) In addition to higher average velocity, the ball will tend to stay straighter when thrown with a four-seam grip.
It’s very important for an older pitcher to experiment with different grips because the movement on the ball will be directly related to the grip. Ideally, the pitcher’s mechanics will not change from one type of pitch to the other. The action on the baseball is determined almost exclusively by the grip.
A Good Start
The following description of our approach to the reverse arm swing is where Paul and I differ from the majority of pitching instruction today. We feel that the reverse arm swing can be “ball first” and the arm can make a smooth transition from hand separation to the point where the ball is above the head. The majority of today’s instruction differs in that the reverse arm action is “elbow first” or “touch the thigh, reach for the sky”. In this approach to throwing the elbow moves to a position even with the shoulder line and the lower arm (below the elbow) moves very rapidly into external rotation (ER) in the shoulder socket.
Paul and I recognize that the “elbow first” reverse arm action can be easier to learn and can be an effective method to throw hard. We just feel that the technique is prone to cause issues with the shoulder and/or elbow when the dynamic ER is executed and the elbow has not reached a position even with the shoulder line. When the elbow is below the shoulder line ER can cause shoulder impingement and the rapid movement into ER can create significant discomfort and potential damage.
In the previous section, we established the correct grip so the next step in understanding our approach to a good reverse arm action is to develop the correct start. The following two pictures of Paul provide demonstrations of the arm action just after beginning the throwing motion. Paul’s body is square to the target (lead shoulder pointed to the plate) and the ball is in the throwing hand, palm down. Careful attention to these two pictures will find Paul’s non-throwing hand (glove hand) also beginning palm down. The throwing arm is quickly at full extension as it moves though a relaxed, continuous swing, headed to a point where the elbow is even with the shoulder.

It’s very important to recognize how early Paul’s hands separate in his throwing motion. In the first picture you can see that Paul’s stride leg is coming down and his throwing hand is already separated from the glove and is behind the back knee. By separating the hands early (top of knee lift), the arm swing can begin early and the reverse arm swing can get the elbow above the shoulder and the ball above the head before the stride foot lands. A teaching thought is that the hands and baseball are like an egg and you “break the egg” or separate the hands on knee lift.
I always think about the first half of the reverse arm swing as if the arm were a piece of rope with the ball attached at the end (or “soap on a rope”). As with a rope, the swing of the baseball will have the ball at the end of the rope following a pendulum arc to the point where the arm is horizontal. The arm doesn’t bend at the elbow at these early points in the reverse swing. Additionally, the ball stays in line with the shoulders as it completes the reverse swing and the throwing hand stays on top of the ball.
It needs to be pointed out, in reference to these photos, that most of the problems that pitchers have at the release point or afterwards are a result of starting late or going wrong early in the reverse arm motion. If you, as the coach or the player, aren’t going to fix the problems at the start of the throwing motion, you shouldn’t try to fix the problems at the finish.

Hands break early on knee lift with palms directed downward (throwing hand on top of the ball)…

The next two pictures show Paul’s arm action later in the throwing motion after the arm has passed horizontal. These pictures show the elbow bending after the throwing arm is horizontal which allows the ball to get above the head. The pictures also show the lead elbow bending so the lead elbow can act as the “rifle sight.” The throwing hand stays on top of the ball all the way to where the ball is above the head. The lead shoulder moves in line with or slightly closed to the target. (The term “closed” means that Paul’s back is slightly turned to the plate rather than his chest being turned to the plate.)

The early break of the hands leads to a smooth, relaxed arm swing because there is plenty of time to get the ball above the head before the stride foot lands. The early separation of the hands cannot be overemphasized to young players. Generally, players break their hands late and then rush through the reverse arm swing portion of the action with tight arm muscles. This is a very common problem and one of the more difficult issues to correct. The result of a late hand separation is that the ball is primarily thrown using the energy developed by the arm rather than by the largest muscles in the body. When the arm is relaxed and has sufficient time to get the hand above the head before foot strike, the “whip” action of the arm can be achieved, driven with the major muscles of the Legs and Torso.
Proper throwing instruction should focus on insuring that the reverse arm swing always gets the arm up to where the elbow is even or above the shoulder and the ball is above the head prior to initiating a strong turning action of the lower and upper body. This ideal position for the arm just before foot strike is shown in the above picture of Paul. In this ideal position, the hand is still on top of the ball with the palm of the hand pointed back toward second base, but the stride foot has not landed. The bend in the elbow occurs after the arm has reached the horizontal position, with the elbow even or above the shoulder.
At the point in the throwing motion where the arms are approximately horizontal, an additional camera angle has been added to address the third critical element of good throwing technique. This picture of Paul shows him prior to foot strike and is taken with the camera aligned parallel with the shoulder blades. The point to emphasize here is that the throwing elbow does not go behind the shoulder line. Even though his upper body is very closed (again, Paul’s back is pointed more to home plate than his chest), the camera clearly shows that his throwing arm and lead elbow are in line with his shoulders.

These are the arm positions that will allow the achievement of a strong position as the stride foot lands. The reverse arm swing has not taken the elbow behind the back at any point, and in addition, the reverse arm swing has maintained the hand on top of the baseball throughout. These essential points, coupled with the proper grip that was described earlier, define the critical elements of the arm and hand movements prior to initiating the actions that will actually accelerate the ball towards the target.

The reverse arm swing should not go behind the back at any point…

It was mentioned earlier that it can be a good teaching aid to think about the throwing motion as consisting of two parts. The first part involves the reverse arm swing where the player works to achieve the ideal position prior to foot strike. Until foot strike is achieved, the arm is largely going away from the intended target.
If the player’s arm gets to a strong position at foot strike he is ready for the Legs and Torso to accelerate the arm. A strong position at foot strike has the ball pointed backward with the elbow above the shoulder and ball above the head (“are you tired of reading this yet?”). Please study all of these pictures of the grip and arm positions leading up to and including foot strike, because we will reference these correct positions continually as the Legs and Torso are discussed.
Proper and Improper Arm Swing
In Line with the Back
In order for you to really grasp the “behind the back” problem mentioned earlier, I’m going to ask you to actually go through correct and incorrect arm swings. Start with a ball in your throwing hand, held palm down against the side of your leg, and slowly swing your arm at full extension in line with the shoulders. Take your arm up to the point where your hand and elbow are horizontal and then continue upward by bending the elbow, keeping the elbow just above the shoulder while the ball moves above the head. At this point, the palm of the hand should be pointed away from your head. You should be able to execute this reverse arm swing with no discomfort or tightness in the shoulder. The hand should stay in line with the shoulders from start to finish of the reverse swing.
Behind the Back (Shoulder Impingement)


Now, return your hand and the ball to the starting position next to your leg with the palm facing downward. Again slowly swing your arm keeping the palm down, except this time take your arm behind your back on the reverse arm swing as shown in this picture of Kolt. You will reach a point in the reverse arm swing (before horizontal) where you no longer can continue an upward motion with the hand if the palm continues to point down. There is a restriction (impingement) generated within the shoulder that limits the height of the arm swing. This impingement is very detrimental to achieving maximum efficiency of the throwing motion.
If you get into this improper position and are going to get your arm to continue upward to where the elbow is above the shoulder, you must first rotate your hand so the palm is pointed upward as shown below. This rotational movement of the hand relieves the impingement in the shoulder socket, allowing you to continue the arm swing to get your elbow above the shoulder; however, the ball will now be pointed toward your head.


If your reverse arm swing doesn’t allow the ball to be pointed away from your head when the elbow is above the shoulder, you will be in a weak throwing position and an optimal upper and lower body motion will not be achievable. Many players develop a sidearm throwing motion because of the reverse arm swing going behind the back and just stopping. Other players develop the throwing technique that we have discussed previously where the throwing action becomes linear with the weight drifting and the body unable to create a dynamic rotational movement. The throwing motion becomes a smooth, linear process that doesn’t achieve maximum velocity.
As mentioned earlier, one major factor that contributes to the “behind the back” reverse arm swing problem is late separation of the hands and a resultant fast reverse arm swing. When a player is late separating his hands in the windup or stretch, the tendency is to sling his arm to the rear quickly to catch up. One characteristic of a fast reverse arm swing is that the arm doesn’t stay in line with the shoulders.
If you remember, in the very first discussions on this site the comment was made that you need to fix the problems with the beginning of the motion. If you are not going to fix these starting problems, you won’t be able to resolve the problems at the finish. The throwing mechanics are complex enough when the player starts properly. When he starts incorrectly with the arm, the mechanics get more and more complex to compensate for weak positions of the arm. Again, great athletes may be able to make some adjustments, but average players need to do all the basics properly.
You Can’t Get Up Too Early
One key concept to get across to young players is that you can’t get your arm up too early: you can only get there too late. I normally will over-emphasize this point by just standing with the throwing arm in the ideal position, elbow above the shoulder, ball above the head, to begin the rest of the throwing motion. The player sees that the same throwing action can result without all the reverse arm motion that leads up to where the foot strike occurs.
Overemphasis or exaggeration of technique is something we use a lot to get a point across. If a player throws sidearm, we’ll try to work with his shoulder angle to get him well above three-quarters in drills and hope the result will be a compromise, three-quarter release point (look at Arm Slot for a more detailed explanation). Similar overcompensation concepts are used for other points in the throwing mechanics.
To continue, the emphasis should always be to get the player’s hands separated at knee lift (ball out of the glove) to start the arm action early. This early separation will allow the arm to get up in position early, with a smooth arm swing. The key checkpoint is that the elbow should be above the shoulder and the ball above the head before the front foot touches the ground (again, are you tired of reading this?).
Stopping the Reverse Swing
Another common problem players have is stopping the reverse arm swing. They typically start correctly and then stop the reverse swing before the elbow gets above the shoulder. We’ve heard some coaches refer to this problem as “sticking.” The end result of a discontinuous reverse arm swing is a non-optimal arm position at foot strike so the elbow is below the shoulder line. A good athlete will “feel” this very weak position of the elbow below the shoulder and will compensate by drifting his weight forward to the front leg to allow his arm to finally get up into a stronger position. This forward weight shift is the most significant characteristic of the blended, linear throwing technique that has been mentioned a couple times so far.
The result of decreased rotational energy is less than maximum velocity. As discussed earlier, great athletes can throw successfully with a blended overall technique and be successful, but average athletes will be more subject to injury and mediocre velocity. The average athlete needs to do everything as close to perfect as possible in order to generate above average velocity and stay injury free.

Troy 103.jpg Troy 104.jpg Troy 105.jpg

In these pictures, Troy exhibits the “sticking” of his reverse arm swing down beside his leg rather than making a continuous reverse arm swing action. Troy is a very strong DII college pitcher that came to Paul for lessons. Once this issue was brought to Troy’s attention he began immediately working to correct the problem.
Elbow Below the Shoulder (Shoulder Impingement)
Having the throwing elbow below shoulder level at foot strike has been described as a “weak” throwing position throughout this website. In order for you to better understand this, I’ll again ask you to do a simple experiment before we proceed.
First, lay flat on your back on the floor or ground with your throwing arm extended to the side. Bend your elbow at a right angle with the hand above the head and position the palm of your hand so that it is facing the ceiling (sky). If you have your elbow in a position even or slightly above the shoulder line and you relax your arm, you will find that the back of your hand, your wrist and the back of your forearm rest on the floor or ground comfortably as shown below. There is no restriction in the shoulder.


Now, if you lower the elbow several inches below the shoulder line (as shown in the second and third pictures) and keep the elbow at a right angle, you will notice the hand and lower part of the forearm come off the floor or ground due to impingement in the shoulder. In other words, there is less flexibility to allow external rotation in the shoulder socket when the elbow is below the line of the shoulders. When you move your elbow back even with or above your shoulder line the hand and forearm will again touch the floor or ground comfortably which means that external rotation is not restricted. Repeat this exercise a few times to gain a clear understanding of the impact of having the elbow below the shoulder during external rotation.



We haven’t discussed external rotation in the shoulder yet as it applies to throwing hard, but external rotation of the arm in the shoulder socket is a major element of any hard thrower’s mechanics (see the following picture of Paul) and the problems associated with external rotation with a low elbow is a major potential problem for all players.


This simple experiment provides you with insight into the need to have a player’s elbow above his shoulder prior to initiating the acceleration phase of the throwing action. You certainly want as little restriction as possible in the shoulder joint to reduce the chance of injury. If you look at any hard thrower when his arm is in the fully flexed position (externally rotated in the shoulder socket), you get an appreciation for the need to minimize restriction in the shoulder socket area. There are Shoulder Exercises on the website that are intended to strengthen the muscles around the shoulder socket while allowing for as much freedom of movement (laxity) as possible, but Shoulder Exercises cannot fix a problem of external rotation with accompanying shoulder impingement.

The elbow should be even or above the shoulder and the palm pointed backward before the stride foot lands…

A point that hasn’t been emphasized yet is the need for the arm, wrist and hand to be relatively relaxed up to and through foot strike. If you will think about the term “whip”, you will envision a leather strap that you swing to maximize the resultant speed of the tip. With a bullwhip, the tip can actually exceed the speed of sound with maximum whip action. While I don’t think the pitcher’s hand can be accelerated sufficiently to break the sound barrier, I would like the coach and player to think of the arm action in much the same way as we do a whip. If the arm is loose and relaxed up to and through foot strike, the major muscles of the body can generate an explosive Legs and Torso rotation that will maximize the speed of the hand (the equivalent of the end of the whip).
Another concept I like to utilize in discussing the arm’s external rotation is the similarity to what happens when a rod is being utilized in casting a lure. With a fishing rod, the backward movement of the rod coupled with the weight of the lure causes the rod to bend and store energy. When the rod has reached its full flex backward and then is whipped forward, the rod continues to bend to store energy. At this critical point, the lure is in a position to be cast forward.
This is analogous to what happens when the arm externally rotates in the shoulder joint. The weight of the baseball coupled with the beginning of the hip turn causes the external rotation in the shoulder. When the arm is fully externally rotated (the forearm is horizontal), the ball is ready to be whipped toward the target. Just like the weight of the fishing lure makes the rod bend, the weight of the baseball and a relaxed arm makes the arm externally rotate in the shoulder socket.  In the Drills page we talk about using a weighted ball and using the weighted ball is specifically to get the pitcher to feel what causes external rotation.
Weighted baseballs are now part of a lot of training programs. We’ve used weighted balls for a long time, but we try to be very careful to utilize the balls to develop a “feel” for how external rotation is developed rather than using weighted baseballs as a strengthening tool for a throwing program. We normally do not throw weighted baseballs much at all.
If the arm is held tightly by the muscles, the player will not be able to obtain maximum external rotation in the shoulder. Without external rotation in the shoulder, the player will not transfer the maximum energy from the body to the arm during upper body forward rotation. Arm speed will not be optimal. When a player achieves a moderately relaxed arm position, full external rotation of the arm in the shoulder socket is allowed to occur.
Over the years I’ve worked with several guys that have had limited external rotation capability in the shoulder. In most of these cases, the athletes had spent a lot of time lifting heavy weights and as a result the muscles were very strong in the shoulders, chest and back. It’s important to understand that upper body strength isn’t a primary asset in throwing. Certainly it’s important to be strong, but throwing requires great shoulder flexibility as shown in the picture above of Paul. Paul always has limited upper body weight lifting to just toning and has essentially eliminated bench presses, rows, military presses and pull downs. Basically, the idea was to eliminate any activity that is going to stress the shoulder joints and limit range of motion.
External rotation in the shoulder is really an essential component of a hard thrower’s technique and one of the most important concepts for coaches and players to understand. With the arm fully externally rotated in the shoulder socket the “shoulder spring” is wound and ready to be whipped forward.
When the arm muscles are tight as the player starts the throwing action, a fluid reverse arm swing doesn’t occur. The result of any restriction in the reverse arm swing is a poor position at foot strike that can cause a push of the baseball rather than a whip of the baseball. A restricted pushing motion generates less velocity than can be achieved with a relaxed arm that is whipped by the strongest muscles of the body. As a coach, you want to get the player to have a relaxed set of muscles in the lower and upper arm prior to and at the stride foot landing position. In all sports, relaxed muscles are fast muscles and this is also true in throwing.
For young players, a relaxed arm and a relaxed grip on the ball are definitely not comfortable concepts. They want to be in control of the ball as we have discussed previously, and they have a definite tendency to “muscle” the ball with their arm and hand. They have thrown using this method for a long time and this is the technique that is comfortable.

The arm, wrist and shoulder needs to be relaxed if the ball is to be “whipped” by the lower body rotation…

As a relaxation test when the player takes the ball back in the reverse arm swing you should be able to pop the back of his hand and have the ball drop free. Occasionally, when I’m throwing batting practice I’ll actually have the ball fall out of my hand during the backward swing. That is the type of relaxation that allows whip of the wrist, forearm, elbow and upper arm.