Wiseman 1
Anatomical & Mechanical Analysis Project of a Baseball Swing
Jake Wiseman
Longwood University
Sharon Menegoni
Wiseman 2
Part I: Background Assignment
In this section I will go through some basic background information. “The pitcher has got
only a ball. I’ve got a bat. So the percentage in weapons is in my favor and I let the fellow with
the ball do the fretting.” This quote by Hall of Famer, Hank Aaron gives every batter in the game
of baseball a positive mindset as they approach the plate to hit. Once they get there, it’s up to the
player’s use of both skill and mechanics to deliver hits. The goal of hitting is simple; to hit the
ball. Hitting involves a combination of strength, balance, timing, and mechanics in order to be
successful at it. These mechanics consist of a number of steps that need to be completed in a
short time. Stance, load, stride, swing, and follow through are the steps designed to help give the
batter a greater chance of hitting the ball (Shepherdson, 1993).
The proper swing starts with a comfortable stance where the batter has complete balance.
To become balanced the feet should be at least shoulder length apart, having the toes pointing
towards home plate, while having a slight bend in the knees (Shepherdson, 1993). To hold the
bat depends on if the batter swings right handed or left handed; if right-handed the right hand is
on top and for left-handed hitters the left hand is on top. To actually grip the bat make sure to
line up your knocking knuckles; which are those that you would knock on a door with. By doing
this you hold the bat with the fingers, and not deep in your palm (Arzola, 2007). When holding
the bat it should be roughly just as far as the rear shoulder. The elbows should be relaxed,
resulting in the lead elbow pointed down and the rear elbow also pointing down. When all of
these steps are put together, you have your stance to start your swing.
The next phase following the stance is the loading phase. During the load phase of the
swing is when the batter begins to really dial in, because the pitcher has just started to wind up.
Wiseman 3
A brief way to describe this step is when the body begins to shift towards the side away from the
pitcher. Most of the body weight tilts towards the rear, making the rear leg responsible for
support. For right-handed hitters most of the body weight is on the right leg, while for lefthanded hitters the body weight is on the left leg. The key is to stay relaxed and only shift the
body weight with the legs, keeping the shoulders level.
The stride is just one step closer to actually hitting the ball, literally. In this phase of the
swing, the batter takes a small stride with the lead foot towards the pitcher. Perform this stride
when the ball leaves the pitcher’s hand (Shepherdson, 1993). What is important about this step is
to keep the foot parallel to the rear foot while being relatively short (Hay, 1993). In addition to
keeping the foot parallel, another thing to keep in mind is the magnitude of the stride. If you
stomp your lead foot down, the body weight shifts back to the front, which would cancel out the
whole loading phase. An easy way to think of the stride is to “test the ice”. When one tests the
ice on water, it is a tap of the toes with the heel off the ground. If one strides with the foot this
way, the weight stays on the back leg and you are ready to swing.
The most difficult phase of the swing is the swing phase itself. The ideal swing is an A to
C motion of the hands. By A to C, point A is where the hands are when the batter begins the
stance; point C is where the bat makes contact with the ball. Instead of moving the hands in an
A to B to C swing, they should jump right from A to C. With the hands moving toward the ball,
the hips begin to rotate, while the angle of the bat drops so that it can come through the zone. As
the batter proceeds to swing, timing is key. When the arms fully extend is where the batter
should make contact with the ball. During this step of the phase the top hand should supinate so
that when contact is made the palm is facing up. What makes this phase even more difficult is
Wiseman 4
that the batter must keep his or her eye on the ball at all times (Perconte, 2009). Having to
perform these steps while concentrating on an object coming at you, can be very difficult.
Contact has been made with the ball, but the swing is not completely finished. Starting
from where the batter makes contact, the next step is to follow through. To do this, keep both
hands on the bat and let your hands follow through the plane of the swing all the way past your
lead shoulder. By following through, the torso should be rotated to where the upper body is
facing the pitcher. This torso rotation and follow through of the hands, gives the batter more
velocity behind the ball, once they have made contact.
Common errors can occur anywhere during the swinging process. They start in the
stance phase and can result from not being balanced, not having proper grip, or having the
elbows up. In the loading phase errors could be from loading too far back to where the batter is
not balanced or leaning the lead shoulder up and dropping the rear one. When batters stride the
instinct is to lead the stride with the toes so that they are towards the pitcher, but this small error
can make a batter lose power in their swing. When the toes point toward the pitcher, this causes
a slight rotation of the hips; which is exactly where the power comes from. The swing step is
where a variety of errors can occur in many different ways, because there are multiple steps
within this one phase. Some common ones include having an A to B to C hand movement,
rotating the hips too soon, dropping the hands before swinging through the zone, or simply just
missing the ball. As for the follow through phase, a few errors could be not following through at
all, rolling the wrists while following through, or following through below the waist instead of
above it.
Wiseman 5
Both beginners and professionals are susceptible to injuries caused from a baseball
swing. The most common injuries during a swing are core muscles. From rotating the torso to
generate maximum power behind the swing the rectus abdominis, transversus abdominis,
internal, and external oblique muscles are easily sustainable to strains (Conte, 2012). Depending
on how bad the injury is, the individual could miss time from playing in future games. Another
common injury that is not preventable is being struck by the ball. Sometimes the pitcher loses
control of the ball and it can hit the batter virtually anywhere.
Part II: Anatomical Analysis
This section is an analysis of the anatomical factors that contribute to a successful swing.
In the sport of baseball, being able to effectively and efficiently swing the bat and hit the ball is a
highly developed skill that takes years of practice to achieve. Hitting involves a combination of
strength, balance, timing, and mechanics in order to be successful at it. “A 90-mph fastball can
reach home plate in 400 milliseconds — or four-tenths of a second” (Coburn, 2007). This leaves
minimal time for a batter to assess the pitch, decide whether to swing or not, and actually start
and carry through the swing; usually no more than a quarter of a second, which can make it easy
to see why this skill can be so difficult to perform effectively and repeatedly. The mechanics of a
baseball swing consist of four main phases; the Stance Phase, Stride Phase, Swing Phase, and
Follow-through Phase (Shepherdson, 1993).
Wiseman 6
Actual Condition
Stance Phase
Joint Position
(Start)
1.) Ankles- Slight
Dorsiflexion (10º)
2.) Knees- Flexion (20º)
3.) Hips- Flexion (20º)
4.) Trunk- Neutral
5.) Elbows- Flexion
(90º Front) (110º Back)
6.) Shoulders- Slight
Adduction, External
Rotation, and Flexion
(Front), Slight
Abduction, External
Rotation, and Flexion
(Back)
7.) Wrists- Neutral
(Front) Slight
Extension (5º Back)
8.) Neck- Rotation (80º
Towards front shoulder)
Stride Phase
Swing Phase
Follow Through
Phase
*Same as Stance Phase
*Same as Joint Position
(End) for Load Phase
*Same as Joint Position
(End) for Swing Phase
1.) Front moves into
plantar flexion, back
remains in dorsiflexion
2.) Front knee moves into
greater flexion, back knee
moves into greater flexion
3.) Front hip moves into
slight internal rotation
and abduction, back hip
moves into slight external
rotation and adduction,
both remain flexed
4.) Trunk moves into
slight rotation opposite of
the pitcher
5.) Remains in flexion
6.) Front shoulder moves
into more adducting and
external rotation, back
shoulder moves into
horizontal abduction and
more external rotation
7.) Front remains neutral
and back remains in
extension
8.) Remains in rotation
towards the front shoulder
1.) Front moves into
dorsiflexion as weight is
shifted back to front foot,
back begins to move into
plantar flexion
2.) Front moves back into
extension, back moves into
greater flexion (35º - 45º)
3.) Front slightly rotates
externally, back internally
rotates ( about 30º - 40º),
both move into neutral
position regarding abduction
and adduction as weight is
shifted toward front leg
4.) Trunk rotates forward
toward pitcher
5.) Both move towards full
extension
6.) Front shoulder moves
into horizontal abduction
and external rotation, back
shoulder moves into more
adducting and external
rotation and drops slightly
to assist with elbow
extension, both are slightly
flexed
7.) Front remains neutral,
back moves from extension
into ulnar deviation
1.) *Same as Joint Position
(End) for Swing Phase
2.) *Same as Joint Position
(End) for Swing Phase
3.) *Same as Joint Position
(End) for Swing Phase
4.) *Same as Joint Position
(End) for Swing Phase
5.) Both move back into
flexion
6.) Front abducts and
slightly externally rotates,
back adducts and slightly
externally rotates
7.) Front moves into
extension, back moves into
a neutral position
8.) Neck moves into a
neutral position due to
forward rotation of the
trunk
Neutral
Joint
Movement
Wiseman 7
8.) Neck remains rotated
towards the pitcher as eyes
follow the incoming pitch
Joint
Movement
(Cont’d)
*Same as Start
1.) Front is plantar flexed
at 20º, back remains the
same as in Stance Phase
2.) Front is flexed at
about 30º, back is flexed
at about 40º
3.) Front hip is in slight
internal rotation and
abduction of about 10º
each, back hip is in slight
external rotation and
adduction of about 10º,
both remain flexed at
about 20º
4.) Trunk moves in
rotation opposite of the
pitcher at about 15º - 25º
5.) Remains in flexion of
about 90º in front, 110º
Back
6.) Front shoulder is
adducting at about 20º,
externally rotating at
about 45º and flexed at
about 45º, back shoulder
is in horizontal abduction
at about 5º - 10º, in
external rotation at about
35º, and flexed at about
45º
7.) *See Stance Phase
8.) *See Stance Phase
1.) Front is slightly
dorsiflexed, back is in
planatar flexion (about 10º)
2.)Front locks into
extension, back is flexed
(35º - 45º)
3.) Front is externally
rotated (about 20º), back is
internally rotated (30º)
4.)Trunk is slightly rotated
towards pitcher
5.) Both elbows are fully
extended
6.) Both shoulders are
flexed (about 40º) and
slightly adducted
7.) Front wrist is neutral,
back wrist is in ulnar
deviation
8.) Neck is rotated towards
pitcher
1.) *Same as Joint Position
(End) for Swing Phase
2.) *Same as Joint Position
(End) for Swing Phase
3.) Front is fully externally
rotated (45º), back is fully
internally rotated (35º)
4.) Trunk moves into full
forward rotation (90º)
5.) Front elbow fully
flexed (150º), back elbow
is flexed (90º)
6.) Front is fully abducted
and slightly externally
rotated, back fully
adducted and slightly
externally rotated
7.) Front is in full
extension, back is in a
neutral position
8.) Neck is in a neutral
position
*All Isometric
1.) Tibialis Anterior,
Peroneus Tertius
2.) Hamstrings Group
3.) Quadriceps Group
4.) Rectus Abdominus,
External Obliques,
Internal Obliques,
Transversus
Abdominus
5.) Biceps Brachii,
Triceps Brachii
6.) Deltoid Group,
Rotator Cuff Group,
Pectoralis Major,
Latissimus Dorsi, Teres
1.) Tibialis Anterior,
Peroneus Tertius (Front =
E, Back = C)
Gastrocnemius, Soleus
(Front = C)
2.) Hamstrings Group (C)
3.) Quadriceps Group (I);
TFL, Glute Med (Front =
C, Back = E); Piriformis
(Front = E, Back = C);
Adductor Group,
Pectineus, Gracilis (Front
= E, Back = C)
4.) Rectus Abdominus,
External Obliques,
Internal Obliques,
1.) Tibialis Anterior,
Peroneus Tertiusn (Front =
C, Back = E)
Gastrocnemius, Soleus
(Front = E, Back = C)
2.) Hamstrings (Front = E,
Back = C) Quadriceps
(Front = C, Back = E)
3.) TFL, Glute Med (Front
= E, Back = C); Piriformis
(Front = C, Back = E)
4.) Rectus Abdominus,
External Obliques, Internal
Obliques, Transversus
Abdominus (C and E)
5.) Biceps Brachii (E);
1.) *See Muscles Involved
for Swing Phase
2.) *See Muscles Involved
for Swing Phase
3.) *See Muscles Involved
for Swing Phase
4.) Rectus Abdominus,
External Obliques, Internal
Obliques, Transversus
Abdominus (C and E)
5.) Biceps Brachii (C);
Triceps Brachii (E)
6.) Deltoid Group (C and
E); Rotator Cuff Group (C
and E); Pectoralis Major,
Latissimus Dorsi, Teres
Joint Position
(End)
Muscles
Involved
Wiseman 8
Major
7.) Extensor Carpi
Radialis Longus,
Extensor Carpi Radialis
Brevis, Extensor Carpi
Ulnaris
8.)Sternocleidomastoid,
Splenius Capitus
Muscles
Involved
(Cont’d)
Exercises
Transversus Abdominus
(C and E)
5.) Biceps Brachii (C);
Triceps Brachii (E)
6.) Deltoid Group (C and
E); Rotator Cuff Group
(C and E); Pectoralis
Major, Latissimus Dorsi,
Teres Major (Front = C);
Supraspinatus (Back = C)
7.) Extensor Carpi
Radialis Longus,
Extensor Carpi Radialis
Brevis, Extensor Carpi
Ulnaris (I)
8.)Sternocleidomastoid,
Splenius Capitus (I)
Triceps Brachii (C)
6.) Deltoid Group (C),
Pectoralis Major, Latissimus
Dorsi, Teres Major (C)
7.) Extensor Carpi Radialis
Longus, Extensor Carpi
Radialis Brevis, Extensor
Carpi Ulnaris (E), Flexor
carpi ulnaris, extensor carpi
ulnaris (C)
8.) Sternocleidomastoid,
Splenius Capitus (I)
Major (Front = E);
Supraspinatus (Back = E)
7.) Extensor Carpi
Radialis Longus, Extensor
Carpi Radialis Brevis,
Extensor Carpi Ulnaris (C)
8.) Sternocleidomastoid,
Splenius Capitus (C and E)
Tibialis Anterior, Peroneus Tertius: Theraband Dorsiflexion (Up Phase = C, Down Phase = E)
Gastrocnemius, Soleus: Calf Raises (Up Phase = C, Down Phase = E)
Hamstrings Group: Leg Curls (C), Leg Extensions (E)
Quadriceps: Leg Extensions (C), Leg Curls (E)
Rectus Abdominus, External Obliques, Internal Obliques, Transversus Abdominus: Sit-Ups (Up Phase = C, Down
Phase = E)
Biceps Brachii: Biceps Curl (Up Phase = C, Down Phase = E)
Triceps Brachii: Biceps Curl (Up Phase = E, Down Phase = C)
Deltoid Group, Supraspinatus: Lateral Arm Raises (Up Phase = C, Down Phase = E)
Anterior Deltoid, Subscapularis: Theraband Shoulder Internal Rotation (Pull Phase = C, Return Phase = E)
Posterior Deltoid, Infraspinatus, Teres Minor: Theraband Shoulder External Rotation (Pull Phase = C, Return
Phase = E)
Perctoralis Major, Teres Major: Bench Press (Up Phase = C, Down Phase = E)
Latissimus Dorsi: Lat Pull-Down (Down Phase = C, Up Phase = E)
Extensor Carpi Radialis Longus, Extensor Carpi Radialis Brevis, Extensor Carpi Ulnaris: Wrist Dumbbell
Extensions (Extend Phase = C, Return Phase = E)
Sternocleidomastoid, Splenius Capitus: Manual Neck Resistance Training (C and E)
Flexor carpi ulnaris: Wrist Dumbbell Curls (Up Phase = C, Down Phase = E)
TFL, Glute Med: Lying Hip Abduction (Up Phase = C, Down Phase = E)
Piriformis: Cable Hip Adduction (Pull Phase = C, Return Phase = E)
Adductor Group, Pectineus, Gracilis: Cable Hip Adduction (Pull Phase = C, Return Phase = E)
*Numbering corresponds to joints, joint movements/positions, and muscles involved in
movements/positions (Joints shown in Joint Position (Start) of Start Phase)
*(C) = Concentric, (E) = Eccentric, (I) = Isometric
Wiseman 9
Wii Condition
Start Phase
Joint
Position
(Start)
Joint
Movement
Joint
Position
(End)
Muscles
Involved
Exercises
1.) Forearm (Humeroradial and Radioulnar
Articulations)- Full pronation
Swing Phase
1.) *Same as Joint Position (Start)
2.) *Same as Joint Position (Start)
3.) *Same as Joint Position (Start)
2.) Wrist (Radiocarpal Articulation)- Extension
(10º)
3.) Elbow- Flexion (90º)
1.) *No movement occurs
2.) *No movement occurs
3.) *No movement occurs
1.) *Same as Joint Position (Start)
2.) *Same as Joint Position (Start)
3.) *Same as Joint Position (Start)
1.) Moves into supination
2.) Moves out of extension and into ulnar
deviation
3.) Remains neutral
1.) Full supination
2.) Full ulnar deviation
3.) *Same as Joint Position (Start)
1.) Pronator Teres, Pronator Quadratus (I)
1.) Biceps Brachii, Supinator (C)
2.) Extensor Carpi Radialis Longus, Extensor
2.) Extensor Carpi Ulnaris, Flexor Carpi
Carpi Radialis Brevis, Extensor Carpi Ulnaris
Ulnaris (C)
(I)
3.) Biceps Brachii (I)
3.)Biceps Brachii (I)
Pronator Teres, Pronator Quadratus: Dumbbell Lying Pronation (Up Phase = C, Down Phase =
E)
Extensor Carpi Radialis Longus, Extensor Carpi Radialis Brevis, Extensor Carpi Ulnaris: Wrist
Dumbbell Extensions (Up Phase = C, Down Phase = E)
Biceps Brachii, Supinator: Dumbbell Lying Supination (Up Phase = C, Down Phase = E)
Extensor Carpi Ulnaris, Flexor Carpi Ulnaris: Dumbbell Ulnar Deviation (Up Phase = C, Down
Phase = E); Wrist Dumbbell Curls (Up Phase = C, Down Phase = E)
Biceps Brachii: Biceps Curls (Up Phase = C, Down Phase = E)
*Numbering corresponds to joints, joint movements/positions, and muscles involved in
movements/positions (Joints shown in Joint Position (Start) of Start Phase)
*(C) = Concentric, (E) = Eccentric, (I) = Isometric
Wiseman 10
Actual Condition
Wii Condition
Wiseman 11
Summary
During the Stance Phase of the actual swing, the player should stand with their feet
parallel and about shoulder width apart, with their knees slightly bent and both elbows flexed.
When the Stride Phase is initiated, the player begins to shift their weight towards their back foot,
rotating their hips and following this rotation with their trunk and shoulders. Once the swing
phase is started, the player begins to shift weight back towards the front foot while rotating the
hips forward, along with the trunk and shoulders once again. Finally, the Follow-through phase
completes the rotation of the hips, trunk, and shoulder and allows the batter to achieve maximum
velocity of their swing. The Wii condition uses the same stance phase for the lower body, but
does not involve any rotation of the hips, trunk, or shoulders and involves minimal movement of
the upper extremities as well. The Swing Phase of the Wii condition only involves manipulation
of the wrist from extension to ulnar deviation and of the forearm from pronation to supination.
As you can see, there are huge differences between the two conditions, the Wii condition having
almost nothing to do with the key mechanics of the actual condition.
Part III: Skill Comparison
This section deals with comparing the Actual Condition and the Wii condition. The goal of both
conditions is to hit a “baseball”, but they both do so in very different ways. The actual condition
involves more phases, practice to successfully achieve, and a greater amount of involved joints
and joint movements when compared to the Wii condition. The Wii condition is a skill that just
about anyone could learn in a matter of minutes, involving very minimal skill or practice to
succeed. Both conditions are distinguished between the muscles they use as well, with the actual
Wiseman 12
condition using almost every muscle in the body, while the Wii condition only uses a few
muscles of one upper extremity. As you can see, both conditions differ greatly from each other in
almost all respects.
Phases
Actual Condition
Four Phases – Stance,
Stride, Swing, and
Follow Through
Ankle, Knee, Hip,
Trunk, Shoulders,
Elbows, Wrists, Neck
Movement Comparison
Wii Condition
Two Phases – Start,
Swing
Forearm (Radioulnar and
Humeroradial), Wrist
Joints
Involved
Stance Phase
Start Phase
 Neutral
 Forearm
Stride Phase
(Pronation)
 Ankles
 Wrists
(Plantarflexion,
(Extension)
and Dorsiflexion) Swing Phase
 Knees (Both
 Forearm
Flexion)
(Supination)
 Hips (Internal
 Wrist (Ulnar
and External
Deviation)
Rotation,
Adduction and
Abduction)
 Trunk (Rotation)
 Shoulders
Comparison
Both have a Start Phase
and a Swing Phase, but
the Wii condition has
no Stride or Follow
Through Phase while
the actual condition
does.
The Actual condition
makes use of just about
the entire body while
the Wii condition uses
only two joints within
the body. The Stance
Phase involves having
basically the same
neutral position in both
conditions, and the
wrist is doing the same
motion in both
conditions.
Both conditions have a
beginning phase that
involves basically the
same neutral positions
for all joints. The only
major difference is that
the body is generally
relaxed in the Wii
condition as compared
to being tense and
prepared in the Actual
condition.
There is no use of a
Stride Phase in the Wii
Wiseman 13
Joint
Movements
Joint
Movements
(Cont’d)
(Exterrnal
Rotation,
Adduction and
Abduction)
 Elbows (Flexion)
 Wrists (Neutral
and Extension)
 Neck (Rotated
toward pitcher
[Neutral])
Swing Phase
 Ankles
(Plantarflexion,
and Dorsiflexion)
 Knees (Extension
and Flexion)
 Hips (Internal
and External
Rotation)
 Trunk (Rotation)
 Shoulders
(Exterrnal
Rotation,
Adduction,
Horizontal
Abduction)
 Elbows
(Extension)
 Wrists (Neutral,
Ulnar Deviation)
 Neck (Rotated
toward pitcher
[Neutral])
Follow Through Phase
 Ankles (Neutral)
 Knees (Neutral)
 Hips (Neutral)
 Trunk (Rotation)
 Shoulders
(Exterrnal
Rotation,
Adduction and
Abduction)
 Elbows (Flexion)
 Wrist (Extension,
condition other than the
loading on the wrist just
before the Swing Phase.
During the Swing
Phase, the Wii
condition has very
minimal movement
involved, with the only
real similarity being,
once again, the motion
of the wrist. The Actual
condition involves
rotation of the hips and
trunk while they remain
widely neutral and
unused in the Wii
condition. The Actual
condition requires a fair
amount of movement at
the glenohumeral joints
as well, with the Wii
condition requiring no
movement whatsoever
of the shoulder. Finally,
the elbows remain
neutral in the Wii
condition as compared
to becoming extended
in the actual condition.
The Wii condition has
no Follow Through
Phase due to not
needing to take any use
of the MA it provides
in the Actual condition.
The Actual condition
makes great use of the
body’s rotation in order
to achieve the greatest
amount of MA
available to exert more
force through the
course of the swing.
Wiseman 14
Muscles
Involved
Neutral)
 Neck (Rotation)
Tibialis Anterior,
Peroneus Tertius,
Hamstrings Group,
Quadriceps Group,
Rectus Abdominus,
External Obliques,
Internal Obliques,
Transversus Abdominus,
Biceps Brachii, Triceps
Brachii,
Deltoid Group, Rotator
Cuff Group, Pectoralis
Major, Latissimus Dorsi,
Teres Major, Extensor
Carpi Radialis Longus,
Extensor Carpi Radialis
Brevis, Extensor Carpi
Ulnaris,
Sternocleidomastoid,
Splenius Capitus, TFL,
Glute Med, Piriformis,
Adductor Group,
Pectineus, Gracilis
Pronator Teres, Pronator
Quadratus,
Extensor Carpi Radialis
Longus, Extensor Carpi
Radialis Brevis, Extensor
Carpi Ulnaris,
Biceps Brachii,
Supinator, Flexor Carpi
Ulnaris
There are clearly not as
many muscles involved
in the Wii condition as
in the Actual condition.
Problems arise in the
Wii condition when
attempting to mimic the
motion of the Actual
condition (swinging
using both hands and
full body motion
provides for poor
results in the Wii
condition). The theory
of getting people to be
more active when using
the Wii fails due to this.
To add to this, the
motion that is required
during the Wii
condition does not
make use of similar
muscles as in the
Actual condition,
causing it to fail in
simulating an actual
baseball swing.
Summary
While the goal is the theoretically the same, these conditions have many major
differences, mainly the actual condition involving a greater amount of skill in that you have to hit
an actual ball moving at a high speed, while the Wii condition is a task that anyone could
perform. During the actual condition more phases occur with movements at almost every joint in
the body; with the Wii condition only having motion at the wrist and forearm over only two
separate phases. There is a much higher potential margin of error in the actual condition as well
Wiseman 15
as a very real chance of injury. The Wii condition really has no negative aspects that could occur
from its actions, aside from possibly losing the game. The only common factor that these
conditions have is the concept of timing in order to hit the ball and that they both include some
sort of stance phase and swing phase, although they both differ entirely from each other. From
analysis of the two conditions, it is clear that the Wii condition does not facilitate as much
required skill or sacrifice in the way of strength, coordination, or commitment as does the actual
condition of swinging a baseball bat and hitting a ball. The clear difference is that the Wii
condition is, in itself, not a true baseball swing. While the creators of the Wii attempted to create
a realistic simulation of playing baseball, they have failed to truly do this in the long run with the
problems encountered when trying to transfer the mechanics of the Actual condition to the Wii
condition.
Part IV: Mechanical Analysis
In this section the swing is broken down into biomechanical principles. Remember in order to
successfully hit a baseball, there are a few things to keep in mind. Hitting involves a
combination of strength, balance, timing, and mechanics in order to be successful at it. These
mechanics consist of a number of steps that need to be completed in a short time. Stance, stride,
swing, and follow through are the steps designed to help give the batter a greater chance of
hitting the ball (Shepherdson, 1993). Proper execution of each phase is crucial for optimum
success. The Stance Phase is where the batter is balanced and awaiting to begin the Stride Phase.
Once the pitcher has released the ball, the batter goes into the Stride Phase, where he steps
toward the pitcher and gets ready to swing. The Swing Phase is where the batter rotates toward
Wiseman 16
the pitcher, making contact with the ball while both arms are fully extended. Once the batter has
made contact they begin the Follow Through Phase, where they simply continue the momentum
of the swing until they are fully rotated. Not only does the body go through these mechanics for
each phase, but it also deals with principles of biomechanics. There are forces exerted by the
body during the process of hitting, as well as forces acting upon the body that impacts each
individual phase of the swing itself. Being able to recognize and understand when these forces
occur is important, so that the batter can maximize the potential of making solid contact with the
ball. A few of these principles include angular kinematics, equilibrium and movement, linear
kinematics, and linear kinetics.
Biomechanical
Principle
Explanation of Impact
a. Angular distance impacts the swing
phase in the total distance that the
bat travels when swinging.
b. Angular Velocity is involved in the
swing phase due to the velocity that
the bat comes through the zone.
c. Angular Acceleration is involved in
the hands of the swing phase; how
Angular Kinematics
quickly the hands accelerate
towards the point of contact, the
quicker the swing is.
Equilibrium
& Movement
a. Mechanical Advantage impacts
how quickly the batter can swing
the bat, based on resistance from
the bat.
How to Optimize
a. Optimizing the angular
distance can be done by
using a shorter bat, so the
head of the bat doesn’t have
to travel quite as far.
b. In order to optimize the
angular velocity, the batter
can use a lighter bat, and by
doing exercises to
strengthen the shoulder by
doing lateral raises.
(Bodybuilding.com)
c. Angular acceleration can be
improved by the path of the
hands during the swing.
This ultimately reduces the
radius of the rotation,
making the hands accelerate
faster.
a. Choking up on the bat is a
great way to optimize
maximum performance. By
choking up, you are
Wiseman 17
Equilibrium
& Movement
(cont.)
Linear Kinematics
Linear Kinetics
b. Center of Gravity, Stability, and
Balance are all closely related
during every phase. If the proper
uses of these concepts are not
followed, then the batter is likely to
fall over when swinging.
b.
a. Linear velocity influences
performance in that if the speed of
the bat moving through the zone is
slow, most likely the batter won’t
make contact with the ball.
b. The trajectory of the bat moving
through the zone is extremely
important. It should be a level
swing, without dropping of the bat
head.
a.
a. Ground reaction force (GRF)
influences the swing in that when
the batter strides out, ultimately he
is timing when he will plant his
lead foot. This causes a shift of the
batter’s weight toward the front,
and is vital transitioning from the
Stride Phase into the Swing Phase
(Fortenbaugh, 2011).
b. Friction of the feet during the
Swing and Follow Through Phases
is pivotal, because this rotation
helps the body gain power.
c. Work impacts the Swing Phase of
the process by pulling the bat
through the zone to hit the ball.
a.
b.
b.
c.
shortening the resistance
arm, while still using the
same amount of force as
with not choking up;
resulting in a quicker, more
controlled swing.
By keeping the feet roughly
shoulder length apart, with
the knees bent, the center of
gravity is fairly low. This
keeps the weight of the
batter back while they are
leaning slightly forward;
keeping the batter stable and
balanced.
To optimize linear velocity,
the batter should use a
lighter, shorter bat. This
will decrease the time it
takes the bat to move
through the zone; it will also
be more controllable.
Optimizing performance
through the bat’s trajectory
can be done by using more
of an “A to C” swing,
meaning keep the elbows
bent and move the knob of
the bat directly towards the
ball.
A longer stride produces
GRF’s with larger,
counteractive horizontal
components. This external
force affects the body’s
velocity. So to limit the
GRFs use a shorter, stride.
In order to optimize this
friction, wear cleats;
depending on ages of
players and particular
leagues, metal spikes may
not be permitted.
Optimizing work is simple,
use a lighter bat while
exerting the same amount of
Wiseman 18
Linear Kinetics
(cont.)
d. Power impacts the distance of
force to swing it.
which the ball travels after contact
d. To optimize power in a
is made. This is the goal behind
swing, the body needs to
every batter’s swing.
wait until the last possible
e. Energy, both kinetic and potential
second, then rotate the lower
are essential for the swing. Your
half as well as the trunk and
potential energy comes from your
shoulders as quickly as
stance in which how tall you stand,
possible, to deliver more
but also how much your weight is
power. P=W/ΔT
shifted to the back, to later move
e. You can optimize your
forward. The kinetic portion is
potential energy by keeping
impacted based on the velocity in
your weight back until you
which the bat moves through.
rotate, as well as using a
f. Momentum is one of the most
heavier bat. This extra
important concepts within a
weight gives you a greater
baseball swing. Along with hip,
potential for power. Kinetic
trunk, and shoulder rotation
energy can be improved by
moementum is where the most of
increasing the velocity of
your power is generated. During
the swing.
the Stride Phase, you are timing
f. To gain excess momentum
when to begin your swing. As the
for a powerful swing, wait
ball approaches, you want to
until the ball is released
ultimately launch your body weight
from the pitcher. As it
forward, so that when your body
approaches, launch your
rotates to swing there will be
body weight forward; this is
momentum. In addition, momentum
the momentum generating
is key in the Follow Through Phase
power. Then when the body
so that you finish your swing.
rotates for contact, you
transition that momentum
into rotation to hit the ball.
Make sure to swing through
the ball and carry your
momentum through the ball
so that there is no wasted
force.
Wiseman 19
Summary
These four principles used in a baseball swing: Angular Kinematics, Equilibrium and
Movement, Linear Kinematics, and Linear Kinetics are basic biomechanical principles that apply
to a variety of skills. The NASPE Standards’ Standard 2 states that, “The physically literate
individual applies knowledge of concepts, principles, strategies, and tactics related to movement
and performance” (NASPE, 2013). As a physical educator and coach, I can utilize these
principles to help my students and players become “physically literate individuals” not just in
baseball, but in all types of physical activity.
Wiseman 20
References
Arzola, G. (2007). Priorities in Hitting. Coach & Athletic Director, 77(2), 44-46
Bernier, D. Baseball batting drills for a tee (part 2). probaseballinsider.com. Retrieved June 05,
2013 from http://probaseballinsider.com/baseballdrillsexcerpt2/
Bodybuilding.com, (2013), Exercise guides – forearm exercises, www.bodybuilding.com,
Retreived June 3, 2013 from
http://www.bodybuilding.com/exercises/finder/lookup/filter/muscle/id/2/muscle/forearms
Conte, S. A., Thompson, M. M., Marks, M. A., & Dines, J. S. (2012). Abdominal Muscle Strains
in Professional Baseball: 1991-2010. American Journal Of Sports Medicine, 40(3), 650656.
Fortenbaugh, D., Fleisig, G., Onar-Thomas, A., & Asfour, S. (2011). The effect of pitch type on
ground reaction forces in the baseball swing. Sports Biomechanics, 10(4), 270-279.
Hay, J. G. (1993). The biomechanics of sports techniques / James G. Hay. Englewood Cliffs,
N.J. : Prentice-Hall, 1993.
National Association for Sport and Physical Education. (2013). National Standards & GradeLevel Outcomes for K-12 Physical Education. Retrieved from
http://www.aahperd.org/naspe/standards/nationalstandards/pestandards.cfm
Perconte, J., & Scioscia, M. (2009). The Making of a Hitter : A Proven and Practical Step-bystep Baseball Guide. Lisle, IL: Second Base Pub.
Shepherdson, N. (1993). Tony Gwynn of the San Diego Padres shows you how to swing a bat
like a champion. Sports Illustrated For Kids, 5(6), 56.
Welch, C. M., Banks, S. A., Cook, F. F., & Draovitch, P. P. (1995). Hitting a baseball: a
biomechanical description. Journal Of Orthopaedic & Sports Physical Therapy, 22(5),
193-201.