Tuesday Morning Scientific Lecture

Hamstring strength, Training ‘sweet spot’ and shared decision making

Nicol van DykRehabilitation Department

#researchinreallife

Disclosure statementHas no relevant financial relationships to discloseWill not be discussing the off-label or investigational use of productsHave no affiliation with Leicester City

1. Train smarter AND harder

2. Hamstring strength

3. Shared decision making

4. Beetroot shots performance boosters

5. Ice Chambers -135°C

Learning objectives from Leicester City

#trainsmarterandharder @TimGabbett

Spikes in HSR (≥ 24km/hr) volumes are associated with hamstring strain injury

Results: HSI risk vs HSR load

Thursday, after training: 40m sprint!

#researchinreallife

1. Train smarter AND harder

2. Hamstring strength

3. Shared decision making

4. Beetroot shots performance boosters

5. Ice Chambers -135°C

Learning objectives from Leicester City

Are you sure you want to do that?

We need to talk about Hamstring

Strength

Argh….

• Hamstring Strain Injuries (HSI) remain the most common muscle injury in football(Hagglund et al 2013, Ekstrand et al 2011, Eirale et al 2013)

Introduction

• Incidence 12-15% (Opar et al 2012)

• 37% of all muscle injuries (Ekstrand et al 2011)

Annual increase 4%

Time-trend of Hamstring injury over 13 years

Jan Ekstrand et al. Br J Sports Med doi:10.1136/bjsports-2015-095359

Copyright © BMJ Publishing Group Ltd & British Association of Sport and Exercise Medicine. All rights reserved.

Cost of an injury in a line up player in a UEFA Champions League team – 20,000 €/dayAverage absence days (28 players)1100 days (50 injuries – 22 days each)

1100 x 20,000 € = 22 million €(Sergei Palkin, CEO Shakhtar Donesk)

@alistairmagowan

3. Introduce a preventative

measure Assess it’s

effectiveness by repeating step 1

1 2. Establish etiology

and mechanisms of sports injuries

1. Establish the extent of the injury problem:• Incidence• Severity

van Mechelen et al 1992

Idea for prevention?

Test it!

Causes?2

4

3

Magnitude

1

van Mechelen et al 1992

• Previous Injury• Increase Age• Ethnicity• Flexibility• H:Q Ratio• Weight/BMI• Height

• Functional Measures• Quadriceps isokinetic

strength

• Hamstring eccentric strength

• Peak Torque• Type of activity

Risk factors for Hamstring Injury

• Previous Injury• Increase Age• Ethnicity• Flexibility• H:Q Ratio• Weight/BMI• Height

• Functional Measures• Quadriceps isokinetic

strength

• Hamstring eccentric strength

• Peak Torque• Type of activity

• Previous Injury• Increase Age• Ethnicity• Flexibility• H:Q Ratio• Weight/BMI• Height

• Functional Measures• Quadriceps isokinetic

strength

• Hamstring eccentric strength

• Peak Torque• Type of activity• MRI

Can Strength be identified as a risk factor for Hamstring

Injury?

– Rod Whiteley– Philipp Jacobsen– Cristiano Eirale– Roald Bahr– Erik Witvrouw– Anne van der Made– Arnlaug Wangensteen– Bruce Hamilton– Hans Tol– Bhavesh Kumar

– Patrice MuxartAcknowledgement

All Teams in Qatar Stars

League (n=14 teams)

2010-2014

No isokinetic tests performed

(n=52 subjects)

Isokinetic Tests during Periodic Health Evaluation

(n=614 subjects) mean follow up of 2.24 years

Q Con 60°/s(n= 556)

H Con 60°/s(n= 555)

Q Con 300°/s(n= 556)

H Con 300°/s(n=556)

H Ecc 60°/s(n=562)

Materials & Methods

4 seasons

614 subjects

1931Isokinetic

Tests performed

Total Injuries 1901st time injuries

131190 injuries

Odds Ratio p-value 95% CI

Q Con 60 0.99 0.06 0.99 - 1.00

H Con 60 0.99 0.17 0.99 - 1.00

Q Con 300 0.99 0.97 0.99 - 1.00

H Con 300 0.99 0.20 0.99 - 1.00

H Ecc 60 0.99 0.12 0.99 - 1.00

Q Con 60 BW 0.71 0.03* 0.52 - 0.97

H Con 60 BW 0.75 0.29 0.43 -1.29

Q Con 300BW 1.10 0.87 0.56 - 1.89

H Con 300 BW 0.75 0.29 0.43 - 1.29

H Ecc 60 BW 0.73 0.04* 0.54 - 0.99

Q Con 60/ H Con 60 0.76 0.32 0.44 - 1.32

H Con 60/ H Ecc 60 1.08 0.90 0.34 - 3.40

Q Con 300/ H Con 300 1.46 0.26 0.76 - 2.79

Q Con 300/ H Ecc 60 1.46 0.35 0.66 - 3.25

Q Con 60 BW 0.71 0.03* 0.52 - 0.97

H Ecc 60 BW 0.73 0.04* 0.54 - 0.99

Results

Q Con 60 Body Weight Effect Size 0.17 6.9 Nm

H Ecc 60 Body Weight Effect Size 0.18 7.1 Nm

Hamstrings Eccentric strength

Quadriceps Concentric strength

are WEAK risk factors HAMSTRING STRAIN INJURIES

Idea for prevention?

Test it!

Causes?2

4

3

Magnitude

1

van Mechelen et al 1992

Health by Exercise, Geo Taylor

1880Prevention AJSM, Petersen et al

2011

130 years!

Nordic Hamstring Exercise

Petersen et al 2011 &van der Horst et al 2015

The Nordic Hamstring RCT’s

Dr. Anthony Shield (@das_shield)

Combined Results

Nordic groups: 753 players → 25 injuriesControl groups: 768 players → 77 injuries

67.5% reduction in hamstring injuries

Nordic Hamstring Exercise

• Low speed• Hip extension• Knee flexion• Muscle targeted

– BF(short head)

– ST

Mechanism of Injury

• High Speed• Hip flexion• Knee extension• Muscle at risk

– BF(long head)

Heiderscheidt et al 2010 JOSPT

It works in practice but not in theory?

Kiezen is verliezen!

Kiezen is verliezen!

Choosing is losing!

T2 rest

T2 shift

T2 after exercise

T2 rest

T2 shift

T2 after exercise

BF ST SM0

5

10

15

20

25

30

35

controlinjury

* P=0.001

* P=0.003

T2 shift in control group and previously injured group

%

35%

18%

9%

Results

ST is most metabolic active in both groups(Schache et al 2013, Oliver et al 2009, McAllister et al 2014)

±80% of Metabolic Activity

More symmetrical pattern

After hamstring injury

rad.washington.edu

• Max eccentric activation

• BF activated & elongated

• Main muscle: ST

• BF is not made for this work ↓ fascicular length↓ stretch tolerant= more likely to fail!

±80% of Metabolic ActivityWhy are BF & ST coupled?

More symmetrical pattern

After hamstring injury

(Onishi et al 2002; Higashihara et al 2010; Schache et al 2013) rad.washington.edu

Choice: Do we only treat the victim, or also the cause?!

We also treat the cause!

#researchinreallife

1. Train smarter AND harder

2. Hamstring strength

3. Shared decision making

4. Beetroot shots performance boosters

5. Ice Chambers -135°C

Learning objectives from Leicester City

Communication

Got it: run fast, score…

Just concentrate

for the next 5 minutes

The Integrated Performance Health Management and Coaching Model.

H Paul Dijkstra et al. Br J Sports Med 2014;48:523-531

Copyright © BMJ Publishing Group Ltd & British Association of Sport and Exercise Medicine. All rights reserved.

Guess Compute ConsequencesCompare to

Experience/Experiment

#researchinreallife

Thank you for your attention

References1. Aagaard P, Simonsen EB, Magnusson SP, Larsson B, Dyhre-Poulsen P. A new concept for isokinetic hamstring: quadriceps muscle strength ratio. Am. J. Sports Med. 1998;26(2):231–237.2. Arnason A, Andersen TE, Holme I, Engebretsen L, Bahr R. Prevention of hamstring strains in elite soccer: an intervention study: Prevention of hamstring strains in soccer. Scand. J. Med. Sci. Sports 2007;18(1):40-48. doi:10.1111/j.1600-0838.2006.00634.x.3. Bahr R. Risk factors for sports injuries -- a methodological approach. Br. J. Sports Med. 2003;37(5):384-392. doi:10.1136/bjsm.37.5.384.doi:10.1136/bjsm.2005.018408.10.4.Eirale C, Farooq A, Smiley FA, Tol JL, Chalabi H. Epidemiology of football injuries in Asia: A prospective study in Qatar. J. Sci. Med. Sport 2013;16(2):113-117. doi:10.1016/j.jsams.2012.07.001.5. Ekstrand J, Hagglund M, Walden M. Epidemiology of Muscle Injuries in Professional Football (Soccer). Am. J. Sports Med. 2011;39(6):1226-1232. doi:10.1177/0363546510395879.6. Ekstrand J, Hagglund M, Walden M. Injury incidence and injury patterns in professional football: the UEFA injury study. Br. J. Sports Med. 2011;45(7):553-558. doi:10.1136/bjsm.2009.060582.7. Freckleton G, Pizzari T. Risk factors for hamstring muscle strain injury in sport: a systematic review and meta-analysis. Br. J. Sports Med. 2013;47(6):351-358. doi:10.1136/bjsports-2011-090664.8. Hagglund M, Walden M, Ekstrand J. Risk Factors for Lower Extremity Muscle Injury in Professional Soccer: The UEFA Injury Study. Am. J. Sports Med. 2013;41(2):327-335. doi:10.1177/0363546512470634.9. Van der Horst N, Smits D-W, Petersen J, Goedhart EA, Backx FJG. The Preventive Effect of the Nordic Hamstring Exercise on Hamstring Injuries in Amateur Soccer Players: A Randomized Controlled Trial. Am. J. Sports Med. 2015;43(6):1316-1323. doi:10.1177/0363546515574057.10. Opar DA, Williams MD, Timmins RG, Hickey J, Duhig SJ, Shield AJ. Eccentric Hamstring Strength and Hamstring Injury Risk in Australian Footballers: Med. Sci. Sports Exerc. 15;47(4):857-865. doi:10.1249/MSS.0000000000000465.11. Opar MDA, Williams MD, Shield AJ. Hamstring strain injuries. Sports Med. 2012;42(3):209–226.12. Orchard J, Marsden J, Lord S, Garlick D. Preseason hamstring muscle weakness associated with hamstring muscle injury in Australian footballers. Am. J. Sports Med. 1997;25(1):81–85.13. Petersen J, Thorborg K, Nielsen MB, Budtz-Jorgensen E, Holmich P. Preventive Effect of Eccentric Training on Acute Hamstring Injuries in Men’s Soccer: A Cluster-Randomized Controlled Trial. Am. J. Sports Med. 2011;39(11):2296-2303. doi:10.1177/0363546511419277.14 .Tol JL, Hamilton B, Eirale C, Muxart P, Jacobsen P, Whiteley R. At return to play following hamstring injury the majority of professional football players have residual isokinetic deficits. Br. J. Sports Med. 2014;48(18):1364-1369. doi:10.1136/bjsports-2013-093016.15. Gabbett Br J Sports Med doi:10.1136/bjsports-2016-09597316. H Paul Dijkstra et al. Br J Sports Med 2014;48:523-531Erik Witvrouw presentation http://www.slideshare.net/MuscleTechNetwork/10-barcelona-2014-erik-witvrouw-4023927718. Schuermans et al BJSM 2015 Biceps femoris and Semitendinosus – teammates or competitors Br J Sports Med 2014;48:1599-1606 doi:10.1136/bjsports-2014-09401719. Van Dyk et al AJSM 2016 Hamstring and Quadriceps Isokinetic Strength Deficits Are Weak Risk Factors for Hamstring Strain Injuries: A 4-Year Cohort study20. http://m.bbc.com/sport/football/36189778

References