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Analysis of Softball Pitching

Marion J.L. Alexander, PhD.
Carolyn Taylor, MSc
Sport Biomechanics Laboratory
Faculty of Kinesiology and Recreation Management
University of Manitoba

Softball Pitching Technique

Softball pitching is the most important skill in the game of softball, as the pitcher
can dominate the game as no other player is able to do. Softball is usually a low scoring
game in which only one or two runs are scored during the entire game, often due to the
dominance of a highly skilled pitcher. Pitchers require several years to perfect their
technique and gain control over the speed and direction of their pitches. Softball pitchers
use an underhand motion that is not as stressful to the shoulder joint as the overhand pitch
used in baseball. Softball pitchers can often pitch several games in one day, and often have
an extended career of many years due to the lower stress levels on the shoulder joint. A
softball pitcher may pitch as many as six 7-inning games during a weekend tournament;
and often the best pitcher on a college team pitches most, if not all of the games each
season (Werner, Guido et al. 2005). This may result in approximately 1200-1500 pitches
being thrown in a 3-day period for a windmill pitcher, as compared to 100-150 for a
baseball pitcher (Werner, Guido et al. 2005).
The softball pitch is a relatively simple motion, consisting of a step forward from the
mound onto the foot on the non pitching arm side, weight shift onto this foot, and rotation
of the shoulders and trunk to a position facing the batter. The pitching arm movement
follows the rotation of the trunk, and is produced by forceful shoulder flexion, medial
rotation and lower arm pronation during release. Skilled softball pitchers can release the
ball at a speed of 55 miles/hour, or 25 m/s. Previous studies have reported an average
release speed of 25.83 m/s, and a range of 23.7 m/s to 27.7 m/s (Werner 1994),
This may be compared to the high speed fastball in baseball pitching, which can be
released at over 100 m/h, or 45 m/s. The ball velocity at release is one of the most
important aspects of pitching skill,

FIG. 1: Softball and baseball pitchers use very different pitching

techniques. The softball pitch on the left is an underhand throw as
opposed to the overhand pitch of the baseball pitcher on the right.
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especially as it relates to injury to the throwing arm. It has been reported that although
softball pitchers may experience fewer injuries to the pitching arm, both types of pitchers
experience distraction forces that are equal to body weight or higher on the shoulder joint
[Alderson, 1999 #81; Werner, 1995 #23;].
Preliminary position
The pitcher must begin the pitch in a position with both feet in contact with the pitching
rubber, and both hands on the ball and must pause for at least one second prior to delivery
of the ball. The shoulders must be square to home plate and the ball held in the midline of
the body. The ball is gripped near the ends of the fingers with the fingers on the seams.
The specific grip is determined by the type of pitch being thrown and varies with the pitch
(Regitano 1982). The pitch begins when the hands separate and the pitching arm moves
back to a position behind the body.
It is important to differentiate between the back leg and the front leg of the pitcher. The
back leg is the leg from which the pitcher pushes off during the pitch- this leg starts on the
pitching rubber and often slides forward from the mound during the pitch. This leg is also
called the pivot foot or the pitching foot, and is the

FIG. 2: Stance phase.

right foot for a right handed pitcher so is the foot on the same side as the pitching arm.
The front leg is the leg onto which the weight is shifted during the pitch, also called the
stride leg. A long step is taken onto the stride leg during the pitch, and all the weight is
shifted onto this leg as the ball is delivered. This is the left foot for a right handed pitcher;
or the non pitching leg.
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In the stance phase the pitcher should assume a wide stance with both feet
touching the rubber but as far apart as possible. This wide stance allows the pitcher to
build up momentum over a greater distance than a narrower stance (Kirby 1969). The feet
are placed about shoulder width apart in the lateral direction
Backswing
The backswing begins as the pitching arm moves
backward, a movement known as shoulder extension, which places
the anterior shoulder muscles on a stretch prior to the forceful
delivery motion (Figure 3). This movement is often accompanied
by trunk flexion, which places the back extensor muscles on a
stretch prior to back extension during the delivery. As the arm
moves back, the pitching foot (the foot on the same side as the
pitching arm) (also called the pivot foot) takes a short step forward.
This step is not allowed (by the rules) to be too long, as the
pitching foot is supposed to be close to the rubber while the
pitching motion is occurring. The pitching foot must also remain
in contact with the ground as it slides forward- it is not supposed to
FIG. 3: Anterior be raised from the ground during the motion forward. When the
shoulder muscles are pitching foot is planted in front of the rubber, the pitching arm
stretched during the starts to move forward (shoulder flexion) toward the front of the
backswing phase of body. The pivot foot turns slightly to the side of the pitcher to
the skill.
allow the hips to rotate to an open position (Werner 1994).
Many windmill pitchers perform illegal movements during the windmill pitch, in
that a long hop or leap is taken onto the back foot prior to planting the front foot for the
pitch. Although a short step forward or slight leg drag is allowed, a long step or leap onto
the back foot is actually illegal. A recent study of Olympic softball pitchers examined the
whether a pitcher was actually airborne, dragged her back foot, or whether there was a
secondary plant and drive (Byrd, Werner et al. 2003). Of the 21 pitchers examined, ten
were airborne as the back foot left the rubber and four had a secondary plant and drive.
Neither of these illegal actions resulted in an advantage in ball velocities when compared
to pitchers using legal techniques. It was concluded that concern over possible increments
in ball velocity due to these illegal movements is not warranted (Byrd, Werner et al. 2003).
It should be noted that umpires seldom call pitchers for this dragging of the back foot, even
though it occurs regularly in many pitchers.
The pitching arm moves forward at the same angular velocity as the other leg (the
non pitching leg) begins to step forward. This motion forward of the front leg is important

FIG. 4: Free leg moves as the pitching arm moves forward. This will help the pitcher push off of the
pitching plate more forcefully.
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in increasing the forceful push-off from the pitching leg (Figure 4). The more forcefully
the free leg and pitching arm move forward, the greater the ground reaction forces down
and back on the push-off leg and the greater the velocity of the center of gravity that can be
transferred to the ball. The acceleration of these limbs forward increases the forces on the
back foot, increases the reaction force that drives the athlete forward.
As the front leg moves forward into the step, the trunk rotates sideways toward the
pitching arm. For a right handed pitcher, the trunk rotates to the right so that it is facing
third base at the top of the backswing, and the opposite shoulder is facing the batter. This
sideways rotation of the trunk increases the range of motion of the pitching arm backwards
and places the trunk muscles on a stretch prior to the forceful rotation back to face the
batter (Figure 5).

FIG. 5: As the pitcher pushes off the pitching plate and steps forward, the pitcher rotates
her trunk away from home plate allowing the pitcher to place the trunk muscles on the front
of her body on a stretch. This position also helps the pitcher conceal the ball from the
batter.
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Force Producing Movements

As the short step onto the pivot foot is taken, the
pitcher may lean forward to stretch the extensor muscles
of the spine. The pitching arm then continues to move
upward in front of the body using shoulder flexion, while
the front leg starts to move downward toward the ground.
The trunk and hips are rotated to a position facing
sideways to the direction of the pitch as the arm circles
upward and forward in front of the body. The back foot
is also rotated so that the toe is now pointing sideways to
the direction of the pitch, which ensures a full rotation of
the hips and trunk sideways (Figure 6).
The pitching arm should remain extended at the
elbow joint during the early part of the delivery, as the
speed at the end of a longer lever is greater assuming that angular velocity can be
maintained (Werner 1993). Since the fully extended arm takes longer to rotate around the
shoulder axis, this allows more time for the action of the trunk to occur. An abbreviated
arm swing with the elbow flexed that occurs faster may be associated with an abbreviated
trunk rotation in which incomplete rotation occurs, which would likely decrease the
velocity of the ball at release.
FIG. 6: Toe is parallel with the
pitching plate and perpendicular When the arm is drawn upward and
to the direction of the pitch. backward during the delivery, the pitching arm should be
kept close to the head and right ear, and should brush the
right hip prior to delivery
(Figure 7). These cues will help
the pitcher to keep the arm on a
straight path (Mogill 1984).
Keeping the arm in this plane
will result in a built in accuracy
measurement for windmillers
(Werner 1993). If the arm
circle is performed so that the
arm passes behind or too far
from the head, the arm will
likely be far from the hip at ball
release. Pitchers who windmill
the arm close to the body tend
to have better
control (Werner FIG. 7: Both elite pitchers shown keep the pitching arm close to the ear as the pitching arm is
1993). Although brought up and around and both brush their hip prior to release of the ball.
initially the
movement at the shoulder consists primarily of shoulder extension, as the trunk rotates to a
position sideways to the plate this movement becomes primarily abduction at the shoulder,
which then becomes adduction as the arm moves back towards the trunk.
The non-pitching arm also makes a contribution to the force of the pitch. The non-
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pitching arm is extended forward during the upswing of the pitching arm. As the pitching
arm moves downward and trunk rotation is started, the non pitching arm can contribute by
driving diagonally downward and backward to assist in forceful trunk rotation (Werner
1994). From the position in front of the body at the start of the pitch, the non throwing arm
can be used to pull the non throwing side backward as the throwing side moves forward
(Figure 8). This produces forceful rotation of the shoulder girdle around the axis through
the spine and horizontal adduction of the pitching shoulder.
The Stride

FIG. 9: Frame 1 illustrates where the pitcher takes off from the pitching plate. In frame 2 the pitchers right toe drags
along the dirt as required by the rules, however this foot bears no weight. Frame 3 shows where the pitcher lands.
Ideally, elite pitchers wish to take up the majority of the pitching circle so they can release the ball as close to home plate
as possible.

As the pitching arm is moving forward and the weight is being driven forward by
the driving back leg, the pitcher will often perform a long hop on the pivot foot in the
direction of the batter (Figure 9). This hop is legal as
long as the back foot is not lifted from the ground. This
hop can often cover several feet, and help to increase the
velocity of the center of gravity toward the batter. This
foot cannot be lifted from the ground during the glide,
but it can only slide forward along the ground. Landing
from the glide onto the pivot foot also helps to load the
rear leg for the final push off toward the batter, so there
should be some flexion of the back leg at the instant of
landing following the glide. The pivot foot turns toward
third base to allow the hips to rotate to an open or
sideways position (Werner 1994). As the weight is
driven forward from the back foot, the center of gravity
follows a straight path toward the target with little
vertical fluctuation until stride foot contact (Werner 1994). The front foot should be
planted in alignment with home plate, and not too far to the left or right so that the
momentum from the drive from the back foot is all directed towards the target. The
orientation of the stride foot should be close to 45 degrees at landing to allow a full range
of hip rotation backwards at the end of the backswing (Werner 1994).
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The length of the stride onto the front foot is an important variable in pitching- the
longer the stride the more skilled the pitcher. The stride length should be in the range of
80% to 100% of the pitchers standing height (Figure 11). A study of eight top US pitchers
reported an average stride length of 73% of standing height with a range from 56 to 86 per
cent (Werner 1994). The longer stride will improve accuracy by flattening the arc at the
bottom of the forward swing and increasing the time during which the pitch can be
released accurately (Kirby 1969).
The body weight is then taken onto the
FIG. 10: Front foot is 45 to the front foot with the toe pointing
plate. at 45 degrees toward the
batter and the knee is extended.
The average knee angle at SFC (Stride Foot
Contact) is 155 degrees
(Werner, Murray et al. 1997). FIG. 11: Length of step is 83% of
The stride knee is extended standing height.
during the weight shift onto
the leg and the front leg
becomes an axis around
which the body can rotate if
hip and trunk rotation are
used during the delivery. This leg usually remains extended throughout the release of the
ball, although hyperextension of the stride knee is not ideal (Werner 1994). Some flexion
of the front leg during delivery of the ball may reduce the forces on the front knee and help
to absorb the forces of delivery. These forces include the forceful weight shift onto the
front foot as well as the rapid rotation of the trunk around the fixed front hip.
The forceful landing on the stride foot in windmill pitching can lead to overuse
injuries to the knee (Werner, Guido et al. 2005). Strength and conditioning regimes are
recommended to strengthen the large muscles of the stride leg to withstand the high
eccentric contraction forces at landing and release.
The front foot is planted (Stride Foot Contact- SFC) just as the arm begins to move
downwards toward the ground. At the instant of stride foot contact the arm is at its furthest
point behind the pitcher. This pattern helps to stretch the anterior trunk muscles of the
pitcher to produce a more forceful trunk rotation toward the batter. The stride onto the
front foot should not be too long; as if the stride is too long the pitcher will be unable to
rotate the hips and trunk to the position facing the batter at release. At the instant that the
arm is at its highest point (top of backswing TOB) the front foot is about to contact the
ground, so the arm and the free leg move downwards at the same time. The time from
TOB to SFC has been reported to be .06 sec (Werner 1994). As the arm starts to move
down toward the ground, the weight is shifted from the back leg to the front leg, and the
trunk rotation from sideways to facing forward is initiated as the weight is being shifted
forward. The weight shift forward is a critical aspect of windmill pitching, and is
important to initiate trunk rotation and to move the weight onto the front foot and into the
direction of the pitch to increase the force applied to the ball (Werner 1995).
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Trunk Rotation in Pitching

In softball pitching the trunk does not rotate as a single unit, but the upper trunk
(shoulder girdle or shoulders) and lower trunk (pelvic girdle or hips) rotate at different
speeds and in sequence. This independent rotation of these two segments is important in
maximizing the contribution of the trunk to ball speed in pitching. When examining the
pitcher, the speed of each of these movements should be calculated separately. It has
been reported that the maximum shoulder rotation speed was 750deg/s with a range of
400 to1200deg/s, while the maximum hip rotation speed was 800deg/s with a range of
300deg/s to1200deg/s (Werner 1995).
As the pitching arm reaches a position parallel to the ground, the weight should be
shifted fully onto the front foot and trunk rotation should be at least half completed (figure
12). Trunk rotation should lead the arm into the release
position, so that the hips are almost facing the batter as the
arm approaches the vertical position at release. In order to
allow for full rotation of the trunk into the release position,
the back foot must be unweighted and allowed to slide
forward toward the front foot. The back foot is often
airborne during this phase of the pitch. Trunk rotation is
then rapidly decelerated prior to release of the ball, so the
trunk is actually stationary through release. This rapid
deceleration of the trunk may provide greater angular
momentum to the arm and help to increase its angular
FIG. 12: Pitching arm is parallel
with the ground and the hips have velocity (Alexander and Haddow 1982).
started to rotate not quite as much A common error in pitching is to retain some
i d
weight on the back leg, which does not allow the hip of the
pitching side to fully rotate forward (Alexander 1998). The back leg should be free of the
ground, or at least sliding forward on the toe to produce optimal weight shift. If the hips
do not rotate forward, as seen in many windmill pitchers (Figure 13), the pitcher will lose

FIG. 13: Many softball pitchers are unable to fully rotate their hips fully and square
them off with the plate. The male pitcher on the left is the only one of the three
pitchers to have his hips squared to the plate.

force that can be produced by the powerful muscles of the trunk (Alexander 1998). The
hips need to rotate to a closed position toward home plate during the delivery phase, and
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this position is facilitated by forceful back leg drive (Werner 1994). The full rotation of the
trunk provides a significant transfer of momentum from the trunk to the pitching arm. In
this position the back foot should be unweighted with the toe on the ground or completely
off the ground (Figure 14).
The amount of hip rotation seen in
skilled windmill pitchers is variable and a
source of controversy among pitching
coaches. Biomechanical principles
suggest that a full range of trunk and hip
rotation is needed prior to release of the
ball in order to attain the maximum
contribution from the trunk to ball
velocity. Hip rotation in which the pelvic
girdle faces home plate at release of the
ball is a desirable technique. Hip rotation
FIG. 14: Both pitchers have all their weight off allows a full contribution from the lower
their back foot. body and trunk into the pitch. However,
the majority of modern windmill pitchers
do not rotate their hips forward to face the batter prior to release of the ball- they keep the
hips facing sideways while the shoulders and pitching arm moves forward through release
(Figure 15). This alters the shoulder movements so that the arm is undergoing shoulder
adduction across the body at release instead of shoulder flexion. This technique forces the
pitcher to throw across her body and lose potential contribution from the trunk and hip
rotation (Werner 1994). It has also been suggested that the range of hip rotation is
dependent on the type of pitch being thrown, with a drop ball requiring less hip and trunk
rotation than a rise ball (Kinne 1987)

FIG. 15: Both pictures are of elite National team players. The pitcher on the left shows better
hip rotation than the pitcher on the right. This can be attributed to the type of pitch thrown or to
personal preference. From a biomechanical point of view, the technique on the left is more
desirable.

There are several possible reasons for this lack of

FIG. 16: This pitcher uses

his hips to hide the ball.
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rotation of the hips (pelvic rotation) to face the batter. It has been suggested that lack of
hip rotation at release will decrease the forces on the pitching shoulder during release.
This is likely due to the decreased stretch on the anterior shoulder capsule when the trunk
is not rotated fully forward prior to the completion of the arm movements. The horizontal
distraction forces acting across the shoulder are decreased when there is less trunk rotation.
This position may also allow the pitcher to hide the ball more effectively until later in the
delivery, making it more difficult for the batter to track the ball.

Arm Movements in Delivery

The shoulder joint is undergoing rapid shoulder flexion and adduction during the delivery,
occurring at a velocity of over 2000deg/s. It has been reported that the peak windmilling
arm speeds range from 1800 to 2400deg/s. This speed of motion at the shoulder joint is
more than twice that reported for elbow flexion speed (Werner 1995). This rapid flexion
produces high shoulder distraction (dislocating) forces that can lead to injuries to the
shoulder. The windmilling speed of the throwing arm just prior to release of the ball
should be decreased just before ball release. Pitchers with faster shoulder rotational
speeds at release were found to have lower ball velocities at release (Werner, Murray et al.
1997). This deceleration of the shoulder rotation may allow some of the speed of the arm
motion to be transferred to the ball (Alexander and Haddow 1982). The deceleration of the
shoulder rotation prior to release requires a strong eccentric contraction of the shoulder
extensors prior to ball release. As the shoulder is decelerating the elbow is flexing to
increase the effectiveness of the shoulder medial rotation and lower arm pronation (Figure
17).
It has been reported that pitchers who have less shoulder distraction force tend to

FIG. 17: The elbow is flexed just prior to release of the ball (top left frame) and will increases the effectiveness of
shoulder medial rotation and pronation of the forearm.
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bend the elbow more at release and into the follow through (Werner 1995). By flexing the
elbow, less pull is created on the shoulder. Some of the energy from the shoulder is
absorbed by the elbow bend, and the circular windmilling motion is stopped more quickly
(Werner 1995). This may be due to the greater shoulder medial rotation that occurs when
the elbow is flexed as compared to the extended elbow. Pitchers who maintain a straight
arm into the follow through tend to continue the windmilling motion long after the ball has
been released. These are the athletes that may encounter shoulder distraction forces equal
or exceeding their body weights (Werner 1995).
Although the elbow is extended for much of the windmill motion, the elbow undergoes
flexion just prior to release of the ball (Figure 17). The average elbow angle for elite
pitchers was found to be 140-165 degrees at release (Werner 1994) (Figure 18). This elbow
flexion helps to increase the moment arm for shoulder medial rotation and therefore
increases ball velocity. The maximum reported flexion velocity for right handed pitchers

was 966 d/s, with a range in the values between 645 to1700 deg/s (Werner 1995).
The pitching arm should remain behind the trunk and in a supinated and laterally
rotated position during the downswing behind the body. The velocity of the ball during
this phase is from the shoulder flexion that is occurring on the downswing, as well as from
the trunk rotation that is occurring. The most active muscle during this phase was found to
be the pectoralis major muscle which was strongly active from the top of the backswing to
ball release (Maffet, Jobe et al. 1997). At a point 2 frames prior to release (.066 s), the
pitching arm begins the critical rotational movements to increase ball speed: lower arm
pronation and upper arm medial rotation. The magnitude of the internal rotation torque
relative to body weight appears to be greater for underhand throwing than for overhand
throwing (Barrentine 1999). It has been concluded that internal rotation of the humerus
produced by this internal rotation torque is a major contributor to ball velocity.
The ball is released in mid pronation and mid medial rotation as this is the point of
peak angular velocity of these movements. Just prior to ball release a maximum internal

FIG. 18: All three pitchers from various developmental stages meet the criteria of elbow flexion.

FIG. 19: The pitching arm starts in a position of lateral shoulder rotation and forearm supination (as seen in frame 1) to a position of
shoulder medial rotation and pronation of the forearm (frame 5).
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rotation velocity of 4600 d/s is reached (Barrentine 1999). These movements are
performed with the elbow slightly bent and the wrist abducted to maximize the length of
the moment arm for these rotations from the axis to the ball. The axis for shoulder medial
rotation passes through the long axis of the upper arm; and the axis for pronation occurs
through the long axis of the lower arm. The flexed elbow and abducted wrist will help to
increase the moment arms about these axes.
The pitcher also performs lateral trunk lean in the direction of the pitching arm
during release- this movement increases the moment arm for both spinal rotation and
rotation around the left hip. The axis for spinal rotation passes through the spine, so that
slight abduction of the arm about the shoulder joint will increase this distance. The axis
for rotation about the left hip passes through the left thigh, and leaning sideways away
from this axis will increase the moment arm for rotation about this axis.

FIG. 20: The lean towards the pitching arm is evident in all four pitchers.

Deceleration of Proximal Segments

The angular velocities of the body segments should be decelerated in order, from
proximal to distal so that each segment can make the maximum contribution to ball
velocity. The trunk reaches maximum angular velocity first, then it will decelerate and
some of the angular momentum generated by the trunk will be transferred to the pitching
arm. The shoulder then reaches maximum flexion angular velocity, which is decelerated
prior to release of the ball. Just prior to ball release, a maximum abduction torque and a
maximum extension torque help to transfer momentum to the most distal segment and
initiate deceleration of the upper arm (Barrentine 1999). During pitching, a peak shoulder
extension torque is reached as elbow flexion is initiated, enabling momentum from the
upper arm to be transferred to the lower arm. The upper arm segment slows as the lower
arm segment speeds up prior to release of the ball.
Shoulder medial rotation and pronation then reach peak angular velocity and then
decelerate, followed by wrist flexion and adduction. The timing of the segmental
movements is that the more proximal segments attain peak acceleration before the more
distal segments. After reaching peak velocity, the proximal segment is decelerated in order
to transfer momentum to the distal segment (Alexander and Haddow 1982). Skilled
pitching may be dependent on the ability of the performer to decelerate proximal segments
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in order. In this way some momentum is transferred from proximal to distal segments.
One implication of this finding is that not only agonist (mover) muscles must be
strengthened in skills of this type, but equally important is the ability of the antagonist
muscles to perform this deceleration of a rapidly moving segment (Alexander and Haddow
1982).
Critical Instant (Release of the Ball)
At the instant of release (REL), the ball should be just anterior to the trunk, or just in front
of the hip on the pitching side. The arm should be just past the vertical position. Just prior
to release, the pitching arm should be in a position of supination and lateral rotation, in
which the palm and the ball are facing sideways (toward third base for R handed). The
elbow should be slightly flexed to produce a maximal moment arm for shoulder medial
rotation. This cocked position of the pitching arm is important to allow for rotation in the
opposite direction during release of the ball. During release, the lower arm should be
pronating and the shoulder medially rotating to increase the velocity of the ball at release.
At release, the arm should be in mid pronation (halfway between supination and pronation)
and mid medial rotation, so that pronation and medial rotation are occurring at the fastest
speed possible. From the side view, the back of the hand should be visible at release to
show that rotation is occurring, as the hand has moved from a palm up position prior to
release to a palm down position following release due to the rotations of the arm (Figure
21).

FIG. 21: Side view of a pitcher in the training to win stage of development. Just prior to release (middle picture) the
hand is palm up, in the middle of its movement from the starting supinated position to the finishing pronated position.

Many skilled windmill pitchers will contact their lateral thigh at the instant of
release, which will stop or slow down the forward progression of the humerus. This
contact with the thigh may help improve accuracy by producing a common point of release
for every pitch and improve consistency of release. This action will also decrease the load
on the rotator cuff muscles in deceleration of the high speed medial rotation and the triceps
in deceleration of flexion of the humerus. Research has shown less rotator cuff activity in
pitchers that contact their thigh with the humerus at release (Werner, Guido et al. 2005).
This may lead to fewer rotator cuff injuries in pitchers that adopt this strategy.
The weight should be all on the front foot at release, the hips (pelvic girdle) should
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be facing forward, and the trunk should be erect and not flexed forward excessively. Many

FIG. 22: Both national

team pitchers do not
rotate their hips fully
prior to releasing the
ball. This position
allows the pitchers to
block their right side and
use their trunk rotators to
pull the upper body
around to face home
plate.

modern pitchers utilize a pitching style in which the hips are not rotated forward during
delivery, but the hips remain facing sideways while the shoulders are rotated forward to
face the batter. This may decrease the contribution from the rotation of the hips (pelvic
rotation), but it may also produce greater force from the trunk rotation by providing a firm
base on which the trunk rotators can pull during delivery Figure 22). As well it may help
the pitcher to hide the ball from the batter longer during delivery.
Follow Through
The purpose of the follow through is to decelerate the pitching
arm over the greatest possible time and distance, to decrease the
force per unit time and decrease the chance of injury. All the
weight should now be shifted to the front leg, and the back foot
should slide forward to a position just behind the front foot.
There should be no weight remaining on the back leg during the
follow through (Figure 23).
The pitching arm should follow through across the body
and upwards, and finish in a position that reaches to at least
shoulder height. The pitching arm will also continue to rotate in
the direction of pronation and medial rotation, to decelerate
pronation velocity over the greatest time
and distance possible. The teres minor
muscle was found to have the highest FIG. 23: Back foot is
muscle activity during this phase, acting unweighted during the
in protraction to prevent excessive follow through to allow the
hips to continue to rotate.
retraction during release (Souza 2005).
Many windmill pitchers experience extreme positions of rotation in
the pitching arm during the follow through, in order to decelerate
the arm rotations over the greatest time and distance possible. As
the follow through ends, the weight is on the front foot, the back
foot has moved up to a position parallel to the front foot, and the
arm is at shoulder level and rotated to a palm down position. The
FIG. 24: Pitcher is
pitcher should be balanced with the trunk erect, the glove up and the
ready to field the
ball after her follow
through.
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eyes on the batter. The feet should assume a ready position with the feet at least shoulder
width apart and the knees flexed in order to field a possible hit back to the pitcher (Figure
24).

Temporal Analysis of Pitching

A temporal analysis is a record of the timing patterns of the different phases of the
windmill pitch. Several of the important timing patterns for the pitch have been reported
(Werner 1994), and are included here. The average ball speed at release was 58 mph (93
kph) for eight elite American female pitchers, with a range from 53 (85) to 62 mph (100
kph) (Werner 1994). These values translate to an average release speed of 25.83 m/s, and
a range of 23.7 m/s to 27.7 m/s.
The average time from the top of the backswing (TOB) until ball release was
found to be .16 seconds. The range of times from TOB to REL for eight pitchers was
found to be .13 to .19 seconds. Average times from TOB to stride foot contact (SFC), and
SFC to REL were found to be .06 sec and .09 sec respectively. On average, the pitch is
delivered from the top of the backswing to ball release in under .2 of a second. The time
from TOB to SFC accounts for approximately 40% of the time, and the time from SFC to
release accounts for 60% of the .16 sec (Werner 1994). From the time the stride foot
touches down until the ball is released only .09 seconds have elapsed, which encompasses
a large number of joint movements moving at a very high velocity.

Measured Variables in Pitching

One of the most consistent parameters in pitching is the elbow angle at ball
release, which was found to be within 20 degrees for eight elite pitchers (Werner 1994).
The average angle for the eight elite pitchers was 139 to 164 degrees. The speed of elbow
flexion has also been found to be important in pitching skill, with the average speed
reported to be 965 degrees per second, with a range from 644 to 1600 degrees per second.
The speed of shoulder flexion just prior to release was found to average 1800 degrees per
second, with a range of 1500 to 2300 degrees per second (Werner 1994)
The peak linear velocity of the center of gravity during the delivery is also a
measure of the power and force of the drive from the mound. An average speed of 3.6 m/s
to 3.4 m/s is common. It is likely that this greater peak CG velocity can assist in
increasing the velocity of the ball at release, and is indicative of a more forceful push-off
from the mound.
Stride angle can be calculated as the angle between a line drawn straight forward
from the back ankle to the plate, and a line drawn from the back ankle to the front ankle.
An angle of zero degrees would indicate that the stride foot landed directly in front of the
pivot foot. An average angle for skilled pitchers is close to 3 degrees, in that the stride
foot lands left of the pivot foot for a right handed pitcher (Werner 1994).
Stride foot orientation is the angle of the stride foot relative to home plate- an
angle of zero degrees would indicate that the foot is pointed straight ahead. The average
 16

stride foot orientation for eight elite pitchers is close to 30 degrees, so the stride foot was
always turned toward a closed position at SFC (Werner 1994)
Knee angle at stride foot contact is a measure of the amount of flexion in
the knee just following contact of the front foot. Values range from 160 degrees,
suggesting a more extended knee at contact, to an average angle of 150 degrees so the knee
was more flexed. This position is related to the individual style of each pitcher, and either
is correct for a particular style.
Shoulder joint angular velocity averaged 1300 degrees per second for each of the 8
pitchers in this study, which is slightly less than the mean values reported for eight elite
pitchers. The previous pitchers attained shoulder speeds of 2000 degrees per second
(Werner 1995); although measuring techniques can affect the values produced in different
studies.
The trunk rotation speed can be measured by two parameters: rotation of the
shoulder girdle and rotation of the pelvis or hip rotation. Since the hips and trunk can
rotate independently of each other, both the upper trunk rotation speed and the lower trunk
rotation speed are calculated (Werner 1995). The average shoulder (referred to as trunk)
rotation speed in this study was 600 degrees per second for subject HN, and 800 degrees
per second for subject SN. These values compare favorably with those reported by
(Werner 1995), with an average trunk rotation speed of 762 degrees per second with a
range of 400 to 1200 degrees / second.
The hip rotation speed in this study was found to be 500 degrees per second for
HN and 600 degrees per second for SN. These are slightly less than the average value for
hip rotation reported by (Werner 1995) to be 796 degrees per second with a range from
300 to 1200 degrees per second.
Elbow flexion velocity is also reported in the literature (Werner 1995) for female
windmill pitchers, with a mean value of 966 degrees per second and range between 645
and 1700 degrees/second. The pitchers in a recent study both attained elbow flexion
values of close to 1100 degrees per second, suggesting that they may have more effective
elbow motion in the pitch (Werner 1995). Another recent study reported the elbow angular
velocity was 2520 deg/s at release of the ball (Kellen 2005). Note that elbow flexion likely
occurs as part of lower arm pronation and shoulder medial rotation, which are difficult to
measure from video film.
 17

References
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Werner, S. L., T. A. Murray, et al. (1997) Report to the coaches: softball pitching at the
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