removing the rust: seasonal runner's workshop...van gent et al. br j sports med 2007...

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Removing Removing the Rust: the Rust: Seasonal Seasonal Runner's Runner's Workshop Workshop 4/12/11 4/12/11 Jenny Kempf, MPT, CSCS Jenny Kempf, MPT, CSCS Amy G. Schubert, DPT Amy G. Schubert, DPT

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Page 1: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Removing Removing the Rust: the Rust: Seasonal Seasonal Runner's Runner's

WorkshopWorkshop4/12/114/12/11

Jenny Kempf, MPT, CSCSJenny Kempf, MPT, CSCSAmy G. Schubert, DPTAmy G. Schubert, DPT

Page 2: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

ObjectivesObjectives

Discuss common running related injuriesDiscuss common running related injuries

Identify causes of running related injuriesIdentify causes of running related injuries

Analyze the biomechanics of runningAnalyze the biomechanics of running

Discuss proper footwear selection Discuss proper footwear selection

Present successful strengthening and training Present successful strengthening and training methods for preventing injuries methods for preventing injuries

Page 3: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

van Gent et al.  Br J Sports Med 2007

Epidemiology

Injury Incidence 19.4‐79.3%Predominant injury location knee

Incidence 7.2‐50%

Other common sitesLower leg = 9‐32.2%Foot = 5.7‐39.3%Upper leg = 3.4‐38.1%

Page 4: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Epidemiology

Knee 42.1%

Foot/Ankle 16.9%

Lower leg 12.8%

Hip/Pelvis 10.9%

Achilles/Calf6.4%

Other 10.8%

Taunton et al. Br J Sports Med 2002

Page 5: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Common Running Injuries

Patellofemoral pain syndromeIliotibial band syndromePlantar fasciitis Tibial stress fractureKnee meniscal injuries

Page 6: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Causes of Running InjuriesCauses of Running Injuries

Page 7: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Causes of Running InjuriesCauses of Running Injuries

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Running Biomechanics

2 main forces that act on the body

Page 9: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Ground Reaction Forces (GRV)

Page 10: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

NewtonNewton’’s 3s 3rdrd Law:Law:

Mutual forces of action Mutual forces of action and reaction between and reaction between

two bodies are equal in two bodies are equal in magnitude and magnitude and

opposite in directionopposite in direction

Vertical GRFVertical GRF

Page 11: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Vertical GRFVertical GRF

Page 12: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Anterior‐Posterior GRF

Page 13: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Braking Impulse

Page 14: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

How can you reduce GRF?

correct commonly seen running faults

Low Stride Ratenovice runners – 150‐160 foot contacts per minuteintermediate runners – 180 foot contacts per minuteelite runners – 200 foot contacts per minute

Page 15: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Low stride rate ‐ Video

Page 16: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Increase Stride RateIncrease Stride Rate

Use a metronomeUse a metronome5 minute cycles 5 minute cycles

2 min stride rate work2 min stride rate work3 min recovery3 min recovery

NO CHANGE IN SPEED NO CHANGE IN SPEED

44--6 weeks to notice change6 weeks to notice change

Page 17: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

How can you reduce GRF?

correct commonly seen running faults

Improve your hip strengthRunner’s with IT band syndrome and patellofemoral pain syndrome have been found to have:

hip weakness Poor hip control when running 

Fredericson et al.  Clin J Sport Med 2000                Dierks et al.  JOSPT 2008                          Ferber et al.  JOSPT 2010

Page 18: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Hip control ‐ Video

Page 19: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Musculoskeletal

Page 20: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Musculoskeletal Fault

Many sources of painDecreased flexibility  **Muscular weakness  **Leg length discrepancyLeg alignment **Flat feet   (pronation)High arches   (supination)

Page 21: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

FlexibilityFlexibility

Has not been proven in literature to be a source of Has not been proven in literature to be a source of pain in recreational runnerpain in recreational runner’’ss

General guidelinesGeneral guidelinesDynamic warm up prior to runningDynamic warm up prior to runningStretching after running for cool downStretching after running for cool down

HamstringsHamstringsHip flexorsHip flexorsCalfCalf

Page 22: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Dynamic Warm up Dynamic Warm up -- VideoVideo

Page 23: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Leg Alignment Leg Alignment

““Knocked KneeKnocked Knee””Literature has shown this can Literature has shown this can be a predictor of running be a predictor of running related injuriesrelated injuries

““Bow LeggedBow Legged””

Page 24: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Hip WeaknessHip Weakness

Buttock muscles need to be Buttock muscles need to be highlightedhighlighted

Knees behind toesKnees behind toesShould feel work in buttock Should feel work in buttock not knees or quadsnot knees or quads

Page 25: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Foot KinematicsFoot Kinematics

~80% of distance runners are rear~80% of distance runners are rear‐‐foot strikersfoot strikers3,143,14

Most of remaining 20% are midMost of remaining 20% are mid‐‐foot strikersfoot strikers

Page 26: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Initial ContactInitial Contact

Page 27: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

More About the FootMore About the Foot……

Pronation occurs during loading to Pronation occurs during loading to ““unlockunlock”” the midthe mid‐‐foot foot joints for effective shock absorptionjoints for effective shock absorption4,54,5

Foot supinates during midFoot supinates during mid‐‐stance; midstance; mid‐‐foot foot ““lockslocks””allowing rigid lever for pushallowing rigid lever for push‐‐offoff55

Pronation is Pronation is normalnormal; it allows the foot to distribute energy ; it allows the foot to distribute energy to entire footto entire foot3,43,4

Page 28: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%
Page 29: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Extrinsic Faults

Page 30: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

SHOESSHOES……

Page 31: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Shoe Support HierarchyShoe Support Hierarchy

Page 32: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

ResearchResearch‐‐ footwearfootwear

Shoe selection based on foot shape has little influence on Shoe selection based on foot shape has little influence on injury riskinjury risk7,117,11

Shoe selection based on Foot Posture Index is overly Shoe selection based on Foot Posture Index is overly simplistic and potentially injurioussimplistic and potentially injurious66

‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐

Visual foot shape assessment has 35% error rate when Visual foot shape assessment has 35% error rate when compared to measurement of actual arch heightcompared to measurement of actual arch height1010

Page 33: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Motion ControlMotion Control‐‐‐‐‐‐‐‐‐‐‐‐‐‐Barefoot/MinimalistBarefoot/Minimalist

Page 34: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Barefoot Running

Habitual shod runners mostly rear‐foot strike (even when barefoot)Habitual barefoot runners often forefoot strikeEven on hard surfaces, barefoot runners who forefoot strike generate smaller collision force than shod rear‐foot strikers

Page 35: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Running SurfaceRunning Surface

Sand, GrassSand, Grass

Hard Paved SurfacesHard Paved Surfaces

TreadmillTreadmill

*Most runners will self*Most runners will self‐‐adjust biomechanicsadjust biomechanics

in response to surface variationin response to surface variation1616

Banked/inclined SurfaceBanked/inclined Surface

Single direction track Single direction track 

Page 36: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Training Error

Page 37: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Training Training RecommendationsRecommendations

Walk‐run progressions

Every other day running

Cross‐training

Avoid speed training

Page 38: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

WalkWalk‐‐Jog IntervalsJog Intervals

Page 39: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Sample Novice ProgramSample Novice Program

Week 1 4 walk, 1 jog repeats x 5 (20 mins total)

Week 2 3 walk, 2 jog repeats x 4 (20 mins total)

Week 3 2 walk, 3 jog repeats x 4 (20 mins total)

Week 4 2 walk, 3 jog repeats x 5 (25 mins total)

Week 5 1 walk, 4 jog repeats x 5 (25 mins total)

Week 6 1 walk, 4 jog repeats x 6 (30 mins total)

Week 7 0 walk, 5 jog repeats x 6 (30 mins total)

Page 40: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Cross TrainingCross Training

EllipticalElliptical

BikingBiking

SwimmingSwimming

Weight liftingWeight lifting

Page 41: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Barefoot Barefoot RunningRunning

Consider a grassy surface or soft Consider a grassy surface or soft track to starttrack to start

Begin with agility drills 2Begin with agility drills 2‐‐3x/week: 3x/week: skipping, sideshuffle, skipping, sideshuffle, 

carioca/grapevine (15carioca/grapevine (15‐‐20 yards x 420 yards x 4‐‐6 6 sets)sets)

Progress to jogging: halfProgress to jogging: half‐‐speed speed followed by followed by ¾¾ speed, etc  (50 yards x  speed, etc  (50 yards x  

44‐‐6 sets)6 sets)

Consider as a warmConsider as a warm‐‐up or coolup or cool‐‐downdown

Consider alternating barefoot runs Consider alternating barefoot runs with shod runswith shod runs

Page 42: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

Ten Percent RuleTen Percent Rule

VolumeVolume

IntensityIntensity

Page 43: Removing the Rust: Seasonal Runner's Workshop...van Gent et al. Br J Sports Med 2007 Epidemiology zInjury Incidence 19.4‐79.3% zPredominant injury location knee zIncidence 7.2‐50%

SummarySummaryPronation is normal part of foot kinematics during running

Selecting shoes based on foot shape does not reduce injury risk

Until evidence proves otherwise, pronation control shoes should be considered unproven to reduce injury associated with running

Barefoot runners have smaller collision force on initial contact

Increases in cadence reduces load to hip and knee during running

Consider walk‐run progressions, every‐other day running, and cross training when initiating a program

10% rule of thumb for running volume and intensity progression

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UW Runners Clinic Services

Providers:  Bryan Heiderscheit, PT, PhD Jenny Kempf, MPT, CSCSAmy Schubert, PT, DPT

Services:  Injury EvaluationPerformance Evaluation

Days:  Tuesdays and Wednesdays

Website:  http://www.uwhealth.org/sports‐medicine/runners‐clinic

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ReferencesReferences1. Novacheck, TF.  The biomechanics of running.  1. Novacheck, TF.  The biomechanics of running.  Gait and PostureGait and Posture; (7):77; (7):77‐‐95.95.

2. Richards CE, Megin PJ, Callister R.  Is your prescription of 2. Richards CE, Megin PJ, Callister R.  Is your prescription of distance running shoes evidencedistance running shoes evidence‐‐based?  based?  Br J Sports Med;Br J Sports Med; (43): 159(43): 159‐‐162.162.

3. Cavanagh, PR.  The Biomechanics of Lower Extremity Action in 3. Cavanagh, PR.  The Biomechanics of Lower Extremity Action in Distance Running.  Distance Running.  Foot & AnkleFoot & Ankle; 1987 (7): 197; 1987 (7): 197‐‐217217..

4. 4. Adelaar, RS.  The practical biomechanics of running.  Adelaar, RS.  The practical biomechanics of running.  Am Jour Sport Med;Am Jour Sport Med; 1986 (14): 4971986 (14): 497‐‐500.500.

5. Novacheck, TF.  The biomechanics of running.  5. Novacheck, TF.  The biomechanics of running.  Gait and PostureGait and Posture; 1998 (7): 77; 1998 (7): 77‐‐95.95.

6. Ryan MB, Valiant GA, et al.  The effect of three different le6. Ryan MB, Valiant GA, et al.  The effect of three different levels of footwear stability on pain outcomes in women runners: a vels of footwear stability on pain outcomes in women runners: a randomized control trial.  randomized control trial.  Br J Sports MedBr J Sports Med; 2010.  Downloaded from ; 2010.  Downloaded from bjsm.bmj.com on 7/8/10.bjsm.bmj.com on 7/8/10.

7. Knapik JJ, Swekler DI, et al.  Injury Reduction Effectiveness7. Knapik JJ, Swekler DI, et al.  Injury Reduction Effectiveness of Selecting Running Shoes Based on Plantar Shape.  of Selecting Running Shoes Based on Plantar Shape.  Nat Strength Cond ResearchNat Strength Cond Research; 2009, 23(3):685; 2009, 23(3):685‐‐697.697.

8. Knapik JJ, Trone DW, et al.  Injury Reduction Effectiveness o8. Knapik JJ, Trone DW, et al.  Injury Reduction Effectiveness of Assigning Running Shoes Based on Plantar Shape in Marine Corpsf Assigning Running Shoes Based on Plantar Shape in Marine Corps Basic Training.  Basic Training.  Am J Sports MedAm J Sports Med; 2010, 38(9): 1759; 2010, 38(9): 1759‐‐1767.1767.

9. Knapik JJ, Brosch LC, et al.  Effect on Injuries of Assigning9. Knapik JJ, Brosch LC, et al.  Effect on Injuries of Assigning Shoes Based on Foot Shape in Air Force Basic Training.  Shoes Based on Foot Shape in Air Force Basic Training.  Am J Prev MedAm J Prev Med; 2010 (38):S197; 2010 (38):S197‐‐S211.S211.

10. Swedler DI, Knapik JJ, et al.  Validity of Plantar . Surface10. Swedler DI, Knapik JJ, et al.  Validity of Plantar . Surface Visual Assessment as an Estimate of Foot Arch Height.  Visual Assessment as an Estimate of Foot Arch Height.  Med & Sci in Sports & ExerMed & Sci in Sports & Exer; 2010: 375; 2010: 375‐‐380.380.

11. Lun V, Meeuwisse WH, et al.  Relation between running injury11. Lun V, Meeuwisse WH, et al.  Relation between running injury and static lower limb alignment in recreational runners.  and static lower limb alignment in recreational runners.  Br J Sports MedBr J Sports Med; 2004 (38):576; 2004 (38):576‐‐580.580.

12. Taunton JE, Ryan MB, et al.  A retrospective case12. Taunton JE, Ryan MB, et al.  A retrospective case‐‐control analysis of 2002 running injuries.  control analysis of 2002 running injuries.  Br J Sports MedBr J Sports Med; 2002 (36):95; 2002 (36):95‐‐101.101.

13. Taunton JE, Ryan MB, et al.  A prospective study of running 13. Taunton JE, Ryan MB, et al.  A prospective study of running injuries: the Vancouver Sun Run injuries: the Vancouver Sun Run ““In TrainingIn Training”” clinics.  clinics.  Br J Sports MedBr J Sports Med; 2003 (37):239; 2003 (37):239‐‐244.244.

14. Lieberman DE, Venkadesan M, et al.  Foot strike patterns and14. Lieberman DE, Venkadesan M, et al.  Foot strike patterns and collision forces in habitually barefoot versus shod runners.  collision forces in habitually barefoot versus shod runners.  NatureNature; 2010 (463):531; 2010 (463):531‐‐535.535.

15. Heiderscheit BC, Chumanov ES, et al.  Effects of Step Rate M15. Heiderscheit BC, Chumanov ES, et al.  Effects of Step Rate Manipulation on Joint Mechanics during Running.  anipulation on Joint Mechanics during Running.  Med Sci Sports ExercMed Sci Sports Exerc; 2010.; 2010.

16. Dixon SJ, Collop AC, et al.  Surface Effects on Ground React16. Dixon SJ, Collop AC, et al.  Surface Effects on Ground Reaction Forces and  Lower Extremity Kinematics in Running.  ion Forces and  Lower Extremity Kinematics in Running.  Med Sci Sports ExercMed Sci Sports Exerc; 2000 (32):1919; 2000 (32):1919‐‐1926.1926.

17. 17. Buist I, Bredeweg SW,  et al.  No effect of a Graded Training PrBuist I, Bredeweg SW,  et al.  No effect of a Graded Training Program on the Number of Runningogram on the Number of Running‐‐Related Injuries in Novice Runners.  Related Injuries in Novice Runners.  Am Jour Spors Med; 2011 (36):33Am Jour Spors Med; 2011 (36):33‐‐39.39.