Biomechanics of Golf Swing By Julie Mastro

Golf Swing Phases: Stance Backswing Downswing Follow Through

Phases of Proper Golf Swing

Golf Swing The golf stance refers not only to your body position when addressing the ball, but also to your body position during the swing. When hitting the ball on different types of terrain, under tree branches, and in heavy rough, you must usually make modifications in the swing. As a result, your stance must change to accommodate the situation.

Golf Swing The key to an affective and dynamic swing is to maintain the lower body and trunk in a stable position. To do this it necessary to have strong muscles in the legs, hips, and lower back. The stronger these muscles are, the easier it is to hold a relaxed stance. (Yessis, 2000) A proper stance allow explosive movements to be made safely, especially for the low back. Having strong quadriceps muscles is important for lower body stability.

Golf Swing To hold the knees and hips level during the swing, there is also a degree of ankle and hip joint flexion. All three leg joints are involved in maintaining the body in a balanced position with the weight lowered and centered over the feet. The knee plays a predominant role in proper alignment.

Stance Phase Stance Phase

Stance Phase Address the Position It is important that we have the proper stance to help create balance. It is vital that we maintain proper balance throughout the golf swig. Align yourself so that feet, hips, and shoulders are parallel to the target line. Feet are shoulder width apart, knees slightly flexed, back is in a straight line, with the hips slightly rotated forward. The club head must be soled directly behind the ball and perpendicular to the target.

Stance Phase Elbows and wrists are extended forward. Slight depression of the arm and scapula as the shoulders roll forward to grip the club.

Stance Phase

Stance Phase Correct golf stance differs between which club you’re using. Driver Iron- Long, mid, and short Wedge Putter

Stance Phase Driver Stance: Feet should be shoulder width apart. Body weight evenly distributed on both feet. Align your body to play off the heel of your left foot (right handed), or right foot (left handed). (Agnew, 2002) Hold the driver with a relaxed grip. A relaxed grip lets the club turn over easily in your hands. If you hold a driver with a strong grip, it generally means you are trying to swing too hard, which can cost distance and accuracy off the tee. (Agnew, 2002) It is important to be aligned “square” to the target. This means the feet and shoulders are parallel to the target line. To check your alignment, place a golf club on the ground along your toes. Leave the club on the ground and walk behind the ball to check that you are aimed correctly. (Agnew, 2002)

Stance Phase Iron Stance: Your weight should be anywhere from a 50/50 split to favoring the front foot slightly. (Agnew, 2002) There should be very little spine tilt away from the target and as a result the shoulders will be fairly level. If the spine is tilted it will cause you to slice or hook the ball. (Agnew, 2002) Your head and ball should be centered between the heels. You need a firm grip with iron play. Grip the club at a 6 on a scale of 1 to 10 on all shots. Loosening the grip increases the likelihood of your shot veering off course. (Agnew, 2002)

Stance Phase Putter and Wedge Stance: Proper alignment is crucial to putting correctly. You want to have your feet, shoulders, hips, and forearms all parallel to the target line of your putt. (Agnew, 2002) Feet should be shoulder width apart. Set-up with 60% of your weight on your front foot, so if you are a right handed player, have 60% of your weight on your left foot and vise versa. (Agnew, 2002)

Upper Body Muscles- Stance Phase Depression and abduction of the scapula Pectoralis minor Serratus Anterior Lower Trapezius Extension of the elbow and forearm Long head Triceps Brachii Lateral Triceps Brachii Medial Head Triceps Brachii Anconeus Extensor Digitorum Extensor Digiti Minimi Extensor Pollicis Brevis Abductor Pollicis Longus.

Upper Body Muscles- Stance Phase Slight wrist adductin during grip both hands: Flexor Carpi Ulnaris Extensor Carpi Ulnaris Flexor muscles of Phalanges Flexor Pollicis Brevis Adductor Pollicis Dorsal Interossei Lumbricals Flexor Digiti Minimi Brevis.

Lower Body Muscles- Stance Phase Slight hip flexion for squat position: Iliacus Psoas Major & Minor Rectus Femoris Sartorius Pectineus Adductor Longus Gracilis. Slight Flexion of Knee Joint: Biceps Femoris Popliteus Semimembranosus Gastronemius Semitendinosus.

Lower Body Muscles- Stance Phase Ankle Dorsiflexion: Peroneus Tertius Extensor Digitorum Longus Extensor Hallicus Longus Tibialis Anterior.

Backswing Backswing

Backswing

Backswing An effective backswing plays an important role in delivering explosive power in the downswing. It is well understood that when a muscle is actively stretched, it will in turn contract with greater force. In golf, the muscles involved in the downswing are placed in a stretched position during the backswing. As a result of the active stretch these muscles accumulate elastic energy, which is given back when the muscles contract in the downswing. When the club is brought up and back during the backswing, it creates a long pathway over which you can produce maximum clubhead speed.

Backswing Shoulder trunk rotation to the rear is one of the most important actions in the backswing. This movement involves the erector spinae muscles on the right side of the lumbar spine. The strength of these muscles determines the amount of shoulder rotation that you can attain when you have adequate midsection flexibility.

Backswing If these muscles are weak or if there is inadequate flexibility in the midsection you will not be able to rotate the shoulders sufficiently to perform a powerful downswing. (Yessis, 2000) When performing the backswing the shoulder should be in line with the target. At the top of the backswing the shoulders should rotate approximately 90 degrees so that the back faces the target. (Yessis, 2000)

Backswing

Upper Body Muscles- Backswing The shoulder joint will adduct on right arm (if left handed) and left arm with abduct. This occurs on a frontal plane, sagittal axis. Right Shoulder Adductors: Lower Pectoralis Major Subscapularis Latissimus Dorsi Teres Major Left Shoulder Abductors: Upper Pectoralis Major Anterior Deltoids Middle Deltoids Posterior Deltoids Supraspinatus

Upper Body Muscles- Backswing Upward Rotation of Scapula: Serratus Anterior Upper Trapezius Middle Trapezius Lower Trapezius Elbow Extensors: Long Head Triceps Brachii Lateral Head Triceps Brachii Medial Head Triceps Brachii Anconeus Elbow Flexors: Long Head Biceps Brachii Short Head Biceps Brachii Brachialis Brachioradialis Pronator Teres

Upper Body Muscles- Backswing Radial Wrist Flexion (Cocking) : Frontal Plane/Sagittal Axis Flexor Carpi Radialis Extensor Carpi Radialis Flexor muscles of phalanges: Flexor Pollicis Brevis Adductor Pollicis Dorsal Interossei Lumbricals Flexor Digiti Minimi Brevis.

Lower Body Muscles- Backswing Right Leg Static Hip Adduction: Pectineus Adductor Brevis Adductor Longus Adductor Magnus Gracilis Left Knee Internal Rotation: Vertical Axis/Transverse Plane Popliteus Semimembranosus Semitendinosus Transverse Tarsal and Subtalar Eversion: Peroneus Longus Peroneus Brevis Peroneus Tertius Extensor Digitorum Longus

Downswing Downswing

Downswing

Downswing The downswing marks the most important phase in the golf swing. What takes place here will determine the outcome of your shot. To generate the force needed to each joint action, you must increase the strength of the muscles involved. This applies to not only your weak actions, but your strong ones as well. The “hip slide” or weight transfer is the first action in the downswing. Generally known as “getting your hips into the shot.” (Yessis, 2000) The main action involved is the right hip joint abduction. This involves the gluteus medius and minimus muscles located on the sides of the hip. In addition, these muscles are involved in holding your pelvis level during the swing. In the stance phase the hips are between the feet. During the backswing the hips remain in place or move back slightly to be closer to the right leg. During the downswing phase, or the “hip slide”, the hips remain level and move forward so that they are over more on the front leg.

Downswing As the weight shift slows down, the hips begin to rotate to the left; they accelerate forward toward the target. When most of the weight is on the left leg, this involves the medial rotators of the left hip joint. The left leg becomes the axis of rotation for the hips to create the longest lever to produce the greatest force. The shoulder rotation is a very powerful action because of the mass being accelerated. The abdominal oblique muscles are strongly involved. In the downswing the shoulders rotate forward toward the target, while the arms are held back. When shoulder rotation occurs simultaneously with the hips, less force is generated. That is why it is important that the hips be cleared and rotated before the shoulder rotation begins.

Downswing The wrist roll. As the arms move into the hitting area, they are held basically straight. The turning hand is a consequence of the arm rotation that takes places in the shoulder joints. There is strong pronation is the right hand and supination of the left. During the downswing not only does the right arm straighten, but the right hand pronates as the arm extend into the hitting area. Supination and pronation can be done separately or at the same time. Wrist break, or unlocking the wrists. The wrists during the backswing are radially flexed to produce a 90 degree angle between the arms and clubshaft. (Yessis, 2000) In the initial phase of the downswing the wrist remain in this position. The wrist break begins when the hands are approximately hip height and ends just prior to contact. In this phase the pinky side of the hand moves toward the forearm. Also known as ulnar flexion.

Downswing Muscles used in downswing

Upper Body Muscles- Downswing Depression of the scapula: Pectoralis Minor Lower Trapezius Rhomboids Left Arm Abduction: Upper Pectoralis Major Anterior Deltoids Middle Deltoids Posterior Deltoids Supraspinatus Trunk Sectin: Internal Obliques External Obliques. Right Arm Adduction: Lower Pectoralis Major Subscapularis Latissimus Dorsi Teres Major

Upper Body Muscles- Downswing Pronation and Supination happen in the vertical axis/ transverse plane. Pronation right forearm: Pronator Teres Pronator Quadratus Supination Left: Long Head Biceps Brachii Short Head Biceps Brachii Supinator Anconeus Ulnar Deviation (uncocking): Extensor Carpi Ulnaris

Lower Body Muscles- Downswing Right Hip Abduction: Frontal Plane/ Sagittal Axis Sartorius Gluteus Medius Gluteus Minimus, Tensor Fasciae Latae.

Follow-Through Follow-Through

Follow-Through Follow-Through

Follow-Through The follow-through ensures maximum speed of the clubhead through the contact area to produce an explosive hit.

Follow-Through When the ball is contacted, your body is basically stationary with only the arms and wrists in action. After contact, the arms continue their forward and upward movement following the clubhead. After the arms, the shoulders continue to rotate forward followed by the hips, and finally the rear foot leaves the ground as your weight ends up on the forward leg.

Follow Through Muscles Used in Follow-Through

Upper Body Muscles- Follow Through Abduction and Adduction of scapula: Pectoralis minor Serratus Anterior Middle & lower Trapezius Rhomboids. Right Arm Glenohumeral Horizontal Adduction: Transverse Plane/Vertical Axis Upper & Lower Pectoralis Major Subscapularis Coracobrachialis Anterior Deltoids. Trunk: Internal/External Obliques Rectus Abdominis.

Upper Body Muscles- Follow Through Lateral Spine Flexion: Frontal Plane/ Sagittal Axis Erector Spinae: Iliocostalis Longussimus Quadratus Lumborum Spinalis

Muscles Used in Follow-Through Lower Body: Internal Rotation of Hip: Gracilis Semitendinosus Semimembranosus Gluteus Medius Tensor Fasciae Latae Piriformis Gemellus Superior Obturator Internus Obturator Externus Quadratus Femoris. Knee Internal Rotation: Popliteus Foot and Ankle: Gastrocnemius Soleus.

Joints Sternoclavicular (SC), Acromioclavicular (AC), and Scapulothoracic Joint: SC and AC joints are anthrodial (multiaxial) joint. SC moves Anteriorly 15 degrees SC posteriorly 15 degrees SC superiorly 45 degrees SC inferiorly 5 degrees SC upward rotation of 45 degrees SC downward rotation of 5 degrees AC protraction/retraction 20-30 degrees (rotational & gliding) AC elevation/depression 20-30 degrees (rotational & gliding) AC upward rotation/downward rotation 20-30 degrees (rotational & gliding) (Floyd, 2010)

Joints Glenohumeral Joint: Known as the shoulder joint: It Moves in all planes and is the most moveable joint in the body. Enarthrodial joint- multiaxial ball and socket. Flexion 90- 100 degrees Extension 40-60 degrees Abduction 90-95 degrees Adduction 0 degrees (prevented by trunk) to 75 degrees anterior to trunk If shoulder is free to move the total combined range would be 170-180 degrees abduction, 170-180 Flexion, and 140-150 horizontal adduction. Internal Rotation 70-90 degrees External Rotation 70-90 degrees Horizontal Abduction 45 degrees Horizontal Adduction 135 degrees

Joints Elbow Joint Radioulnar Joint Trochoid Joint (pivot joint) The elbow may be thought of as two interrelated joints: the humeroulna and the radiohumeral joints. Involves primary movement between the articular surfaces of the humerus and ulna. Ginglymus Joint (hinge joint) Extension 0 degrees Flexion 145- 150 degrees The radial head rotates around in its location at the proximal ulna. Trochoid Joint (pivot joint) Supination 80-90 degrees Pronation 70-90 degrees

Joints Wrist Joint Finger Joint Codyloid Joint- (Floyd, 2010) Wrist motion occurs between the distal radius and the proximal carpal row, consisting of the scaphoid, lunate, and triquetrum. Codyloid Joint- Flexion 70-90 degrees Extension 65- 85 degrees Abduction 15-25 degrees Adduction 25- 40 degrees (Floyd, 2010) Each finger has 3 joints, while the thumb only has 2. Finger Joints: Metocarpophalangeal (MCP): Condyloid joint: has 0-40 degrees extension/85-100 degrees flexion. Proximal Interphalangeal (PIP): Ginglymus joint: has 0 degree extension/90- 120 degree flexion. Distal Interphalangeal (DIP) Ginglymus Joint: 0 degree extension/80-90 flexion. Iinterphalangeal (IP) & Carpometacarpal (CMC): Flexion 80-90. CMC- Abduct 50-70, flex 15-45, extend 45 degrees.

Hip Joint and Pelvic Girdle Joints Hip Joint and Pelvic Girdle Anteriorly the pelvic bones are joined to for the symphysis pubis, an amphiarthrodial joint. Posteriorly the sacrum is located between the two pelvic bones and forms the sacriliac joint. The hip joint is an enarthrodial joint. It is formed by the femoral head inserting into the socket provided by the acetabulum of the pelvics. Flexion 130 degrees Extension 30 degrees Abduction 35 degrees Adduction 0-30 degrees External Rotation 50 degrees Internal Rotation 45 degrees

Joints Knee Joint Tibiofemoral Joint Ginglymus Joint (Trochoginglymus) For internal and external rotation to occur, the knee must be flexed approximately 30 degrees or more. Extension 0 degrees Flexion 140 degrees Internal Rotation 30 degrees External Rotation 45 degrees

Joints Foot and Ankle Joints Tibiofibular Joint: Formed by the tibia and fibula. Amphiarthrodial Joint Talocrural Joint: Also known as the ankle joint and is made up of the talus, distal tibia, ad distal fibula. Ginglymus Joint Plantar Flexion 50 degrees Dorsal Flexion 5-15 degrees Metatarsophalangeal Joints (MP): Where the phalanges joint the metatarsals. Condyloid Joint Flexion 45 degrees/ Extension 70 degrees Abduction variable 5-25/ Adduction variable 5-25 degrees Interphalangeal (IP): Ginglymus Flexion 90/ Extension 0 degrees Distal Interphalangeal (DIP): Flexion 60/ Extension 30 degrees (Floyd, 2010)

The Key to Golf Longevity The key to golf longevity is strong back strength. A bad back can put a crimp in not only your swing, but also your ability to continue playing the sport. Studies have found that most back injuries are due to improper posture in the stance phase. (Yessis, 2000) Poor posture can lead to an unnatural curvature of the spine.

Key to Golf Longevity Some things that can cause a curvature are tight hamstrings, hip flexors, and quads. Or a weak transverse abdominus which is a core stabilizer muscles that acts a belt for our low back which could injure the low back on the swing phase.

The Key to Golf Longevity

Stretches to Lengthen the Back These spinal stretches are highly beneficial Cat Cow Stretch: Spine Twist:

Stretches to Lengthen the Back

Exercises to Strengthen the Back These exercises are recommended to strengthen the back. Back Raise-

Exercises to Strengthen the Back Good Mornings:

Exercises for Upper Body Biceps Triceps/ Tricep Kickback

Upper Body Push Ups:

Exercises for the Shoulder

Exercises for Shoulders Rotator Cuff:

Shoulder Stretches

Lower Body Stretches Quadriceps Stretch: Psoas Stretch: Hamstring stretch:

Exercises for Legs Squats: Jump Squats:

Exercises for Hamstring and Gluts Gluteus

Exercises for Oblique's and Abdominals Basic Sit-Up Oblique Twists: Plank Twists:

Citations Floyd, R. T. (2010). Structrual kinesiology. (Eighteenth ed.). New York, NY: McGraw-Hill. Yessis, M. (2000). Explosive golf. Lincolnwood, IL: Contemporary Publishing Group. Agnew, T. (2002). The kinesiology of golf. Chicago, IL: Down East School of Massage McHardy, A., & Pollard, H. (2005). Muscle activity during the golf swing. Sydney, Australia: Macquarie Injury Management Group.