Evaluation and Analysis of the Swimming Athlete. Dan Enz PT, LAT

Transcription

1 Evaluation and Analysis of the Swimming Athlete Dan Enz PT, LAT

2 Objectives Review Swimming Prevalence and injury epidemiology History and physics of swimming biomechanics ID common stroke dysfunctions along with physical causes and outcomes Treatment Pearls

3 Swimming Prevalence Greater then 250,000 swimmers registered in USA swimming More then 38,000 members in US Masters Swimming Estimated over 5 million above and beyond USA Swimming in High School and Summer League

4 Freestyle most common training stroke fore all Collegiate swimmers can swim up to 20,000 yards/day stroke per 25 yds 10,000 yards, ~ 4,000 arm rotations Proper stroke technique is essential Training

5 Injury Epidemiology Cole reported 30% shoulder injury rate out of 325 swimmers over 1 year Bak et al reported a 38% incidence of shoulder injuries per year in swimmers Pink et al reported a 47% lifetime incidence of shoulder injuries in collegiate swimmers and a 48% in masters swimmers Yanai and Hay showed that 40% of impingement occurs during recovery, 40% at entry, 20% during the pull

6 Also termed crawl, or front crawl Long axis stroke Majority of competitive swimmers training Changed through the years Phases of stroke Catch Pull Push Recovery Freestyle

7 History of Freestyle Up to the 70 s propulsion was described by Newton s 3 rd law, for every action there is a an equal action in the opposite direction As the hand and arm push against the water, the water pushes back and propels the body forward

8 History of Freestyle Counsilman performed 2 dimensional biomechanical analysis in the 70 s Showed propulsion was due to lift Bernoulli s Principle S shaped underwater pull Model failed to consider body rotation

9 History of Freestyle In 1994 Rushall et al performed 3 dimensional analysis of freestyle swimming Found that propulsion was due to drag forces and Newton s 3 rd law after all Accounted for body rotation which decreases surface area and accounts for the S shaped pull Concept of a straight through pull developed

10 History of Freestyle In 2001 Riewald showed that propulsive drag forces produced by the hand stop before the hip and lift force is negligible through out the stroke New coaching: Early catch early exit with degrees of roll per side

11 Freestyle Entry/Catch Enter in the plane of the axilla Hand enters at wrist level of a straight arm, then elbow straightens to get long and glide Opposite arm pull at entry Slight internal rotation pitch to the hand ~40 deg. Soft and slow in the beginning Feeling of holding the water Opposite leg kick Elbow bends and remains towards the surface on catch

12 Early Pull/Pull Elbow bent for pulling surface and IR Opposite arm finishing recovery Arm vertical at mid stroke Pulling body past a stationary arm Straight pull Body rotation Accelerate stroke Freestyle

13 Freestyle Push From forearm vertical to the hip Push the body past the arm Arm continues to accelerate Power is through the core and axial rotation Need > 40 degrees to clear the hip Elbow exits first

14 Freestyle Exit/Recovery Elbow exit first then 5 th digit Trunk axial rotation so that arm doesn t horz. Abduct past the plane of the body Elbow leads initially in recovery then hand

15 Kick Important for propulsion and takes stress off shoulder Legs rotate with body Power is from hip and knee ext. Need ankle dorsiflexion 2beat/4beat/6beat Collegiate swimmers can perform s at 1:30 Freestyle

16 Freestyle Head Position/Breathing Head traditionally slight cervical extension, however, some say look at the bottom of the pool Effects feet position, shoulder stress When not breathing the head stays quiet Breath at the beginning of recovery inhale only Bilateral breathing

17 Freestyle/Head Position

18 Freestyle

19 Typical Causes of Impingement Yania and hay in dimensional videography Found that swimmers at high risk of impingement had 3 characteristics Large amount of internal rotation during pulling Late initiation of ER during recovery Small amount of axial rotation

20 Where and When do They Hurt? Tissue involved helps ID stroke dysfunction Phase in the stroke ID s stroke dysfunction Out of water flaws Entry and Pulling flaws Novice swimmer flaws

21 Freestyle Stroke Flaws Out of Water Thumb First Entry Physical Outcome 1. Impingement of supraspinatous, LHB, anterior structures Physical Cause 1. Over developed IR 2. Weak ER 3. Poor motor program 4. Coached for improved catch

22 Freestyle Stroke Flaws Out of Water Excess IR in Recovery Physical Outcome 1. SA impingement/ LHB Physical Causes Weak ER RTC fatigue Posture Motor program or poor coached drill

23 Freestyle Stroke Flaws Increase Horizontal Abduction in Recovery Out of Water Physical Outcome 1. Anterior micro laxity/instability?? 2. LHB traction 3. Internal Impingement Physical Causes 1. Decrease axial rotation 2. Anterior GH laxity 3. Poor motor control/drill

24 Freestyle Stroke Flaw In the water Crossover Entry/Pull Physical Outcome 1. Increase time in the impingement zone Physical Causes 1. Hypermobility in GH joint 2. Poor ST stability 3. Poor axial rotation 4. Poor motor awareness

25 Freestyle Stroke Flaws In the water Poor Timing: Start pull to early Physical Outcome 1. To wide early, cross mid line late 2. Increase IR, extension demand 3. Impingement, Ant. Tension and laxity Physical Cause 1. Poor core strength 2. Poor balance in water, push down to get head out of the water 3. Poor motor program

26 Good Timing

27 Straight arm Pull Freestyle Stroke Flaws Physical Outcome 1. Anterior laxity 2. Increase lever arm to force arm into impingement 3. Radicular symptoms Physical Cause 1. Want to push against buoyancy 2. Decrease IR 3. Poor momentum 4. Week IR 5. Poor Drill In the water

28 Freestyle Stroke Flaws In the water Pull to wide Physical Outcome 1. Increase IR 2. Impingement, LHB Physical Cause 1. Flat 2. Poor motor awareness

29 Freestyle Stroke Flaws Novice Swimming Flat Swimming Flat Physical Outcome 1. Increase horizontal abduction on recovery Anterior shoulder laxity LHB tensile stress Internal impingement 2. Increase IR for pull Posture RTC dysfunction Physical Causes 1. Anterior pelvic tilt 2. Poor Core strength 3. Poor kick 4. Poor motor program

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31 Freestyle Stroke Flaws Lateral Trunk movement Novice Physical Outcome 1. Increase resistance 2. Increase pull force secondary to decrease core involvement for pulling 3. Repetitive spine loading Physical Cause 1. Poor oblique strength 2. Cross midline 3. Motor program

32 Freestyle Stroke Flaws Novice Insufficient Kick Physical Outcome 1.Increase demand on shoulder to pull Physical Cause 1. Decrease ankle PF 2. Poor hip strength 3. Insufficient core strength 4. Not in a cylinder

33 Freestyle Stroke Flaws Unilateral Breathing Physical Outcome 1. Impingement to opposite arm 2. Imbalance core strength 3. Poor timing Physical Cause 1. Imbalance core strength 2. Poor timing

34 How do we solve this puzzle?

35 Why Shoulder Pain Monad, Pink, Wadsworth, Su all have shown Scapular involvement Jobe: Micro trauma and secondary impingement Sein: All volume and SS tendonopathy Many Others only show scapular mechanics changes after pain Borsa showed no difference in Laxity painful vs. non painful swimmers Why can some swimmers swim yds/day without pain

36 What about this? Kaneoka et al AJSM 56 elite swimmers (35 men, 21 women) Mean age 19.6 years 38 age matched controls MRI lumbar spine 68% elite swimmers vs 29% controls had sig. disc degeneration with L5,S1 most common

37 Things to consider in Evaluation Age/gender Training Stroke Phase of the stroke Duration and speed to pain Mobility swim specific What are you going to look at?

38 What are we evaluating? THINK COMPRESSED S Yes his shoulder is sore! From the ground up! What is shortened, what s lengthened What is found at the pelvis/lumbosacral What is found at thoracic spine, scapula What is found at c spine Now tell me why his shoulder hurts

39 Can we do Better then This??

40 Treatment PEARLS Treat what you find Think of the demands of your athlete Make sure your treating What you think you are Apply knowledge of stroke dysfunction

41 Treatment PEARLS Pelvis Core What to do with latismus, pectoralis, and hip flexor tightness What to do with core stability

42 Treatment PEARLS

43 Treatment PEARLS Thoracic Spine rib Eval IR/ER ringing effect of rib cage Hypomobility causing hypermobility

44 Thoracic Spine/rib cage/st Treatment PEARLS

45 Treatment Pearls Shoulder girdle

46 Shoulder Girdle Treatment PEARLS

47 Core/stability/body position sense Treatment PEARLS

48 Treatment PEARLS Dynamic stability Posterior cuff vs. pulling Incorperate core

49 Stability Proprioception Add core stability

50 Remember Understanding sports biomechanics Drives evaluation Drives movement assessment Drives Treatment Drives neuromuscular re education Drives Success

51 References Townsend,Jobe, Pink, Perry. EMG analysis of GH mm. ASJM 1991; 19: Mosley, Jobe, Pink, Perry, EMG analysis of scapular mm during Rehab AJSM, 1992;20: Rushall et al. Reevaluation of forces in swimming. J of Swimming Research 1194;10:6 30 Rupp et al. Shoulder problems in High Level Swimmers Int. J Sports Med.,Vol 16; McMaster: Swimming Injuries; Sports Med 1996;22(5): Kenal, Knapp: Rehabilitation of injuries in competitive swimmers Sports Med 1996; 22(5):337 47

52 References Yanai, Hay. Shoulder impingement in front crawl swimming: Med Sci. Sports Exerc. 32:30 40, 2000 Pink, Tibone: The painful Shoulder in the swimming Athlete. Ortho clinic of NA April 2000; 31(2) Johnson et al: Swimming Biomechanics and injury prevention. Phys Sportsmed 2003; 31(1) Swimming Biomechanics and prevention USA swimming Cole, Johnson, Fredrickson Injury Incidence in competitive swimmers Presented 2002 USA Sports medicine Society and American Swim Coaches Association meeting Borsa et al. Sonographic Measurement of GH laxity in collegiate Swimmers and age matched controls 2005 AJSM

53 References Sein et al. Shoulder Pain in Elite swimmers: Primarily Due to Swim Volume induced Supraspinatus tendinopathy. Br. J. Sports Med May 2008 Kaneoka et al. Lumbar Intervertebral Disk Degeneration in Elite Competitive Swimmers AJSM 2007