1 Flexibility (Testing and Training) - PowerPoint Presentation

1. 1Flexibility (Testing and Training)

2. 2OutlineDefinitions of FlexibilityWarm up vs StretchingFactors that influence Range Of Motion (ROM)Physiology and Biomechanics of FlexibilityAssessment of FlexibilityBenefits of FlexibilityFlexibility program variables

3. 3Definitions of Flexibility“ability to be bent, pliable” The New Shorter Oxford English Dictionary (1993)Functional ability of a joint to move through its full range of motion (ROM) (ACSM 2010)Functional ability - movement without incurring pain or a limit to performance“The ability of a joint to move through its full range of motion” (Brooks et al. 2000).There is little agreement about the definition of “normal” flexibility.Optimum flexibility is hard to assess, and varies with sport. More ROM is not necessarily better.Inadequate flexibility can decrease performance of activities of daily living as well as some sports.

4. 4Further DefinitionsFlexibility refers to the extensibility of periarticular tissues to allow normal or physiological motion.Laxity refers to the stability of a joint (Saal, 1987). Excessive joint laxity can be the result of injury or heredity condition.Hypermobility refers to a range of motion in excess of the accepted normal motion in most of the joints (Alter, 1996).

5. 5Types of FlexibilityStatic flexibility: ROM about a joint with no emphasis on speed.Ballistic flexibility: usually associated with bobbing or bouncing motion.Dynamic (functional) flexibility: ability to use ROM in the performance of a physical activity.

6. 6Warm upWarm up prepares athletes for training or competition May reduce the risk of injury and improve performanceIncrease muscle temperature, core temperature, and blood flowImpact on performance;Faster muscle contraction and relaxationIncreased rate of force developmentInc muscle strength and powerLowers viscosity of muscleImproved O2 delivery (Bohr effect - temperature)Increased blood flow to active muscleIncreased rate of metabolic reactionsNSCA - Essentials of Strength Training and Conditioning 2008

7. 7Components of a Warm upWarm up should be gradually progressive without causing fatigueGeneral - 5 to 10 minutes low intensityMy be sport specific (jogging / ball dribbling)Raise HR, ventilation, blood flow, deep muscle temperature and reduce viscositySpecific - 10 minutes Dynamic stretching (mobility drills) - sport specific movements (examples near end of lecture)Progressively increase intensity - sprint drills, jumpingHigh intensity dynamic exercises may facilitate subsequent performanceStatic Stretching in warm up may decrease subsequent performanceDecreased force, power, running speed, reaction and movement time, enduranceNSCA - Essentials of Strength Training and Conditioning 2008

8. 8Factors that Influence ROMRange of Motion (ROM) is joint specific, and results from a combination of factors; including adequate warm-upStructure of Joint - (47%)Determines degree of freedom of movementHinge vs ball and socket jointRigidity of Ligaments (10%)Help stabilize and protect joints from excessive motion during dynamic movementsRestrict ROM and offer support at end of ROMExtensibility of periarticular tissues - muscle and tendon (41%)Component that can be modified most significantly and influenced by flexibility trainingLength of muscle and level of neurological innervation in muscle being stretched

9. 9Other influences on FlexibilityNervous system activitySudden stretch of a muscle stimulates muscle spindle and reflex contractionImportant for proprioception and controlling muscle lengthSlow static stretches, spindle activity increases for about 10 sec then diminishes greatly This can also help alleviate muscle crampsIntracapsular structures articular cartilage and synovial membranes facilitate smoothness of movement while maintaining integrity of jointSoft tissue compression of soft tissue by adjacent segments contributes to termination of ROMEg obese or very heavy musculature

10. 10Limits due to Muscle StructureContractile Components of MuscleSacromere (S) resting length 2.30mmMaximum extensibility 3.50mm (150%)Hence increased extensibility occurs by an increase in the # of sarcomeres in seriesImproper Muscle BalanceStretch short muscle (flexibility assessment)Strengthen weak muscle (strength assessment)

11. 11Total Length-Tension CurveText Fig.3-18

12. 12Limits due to Connective TissueConnective tissue surrounds muscle fibers (fascia), and in a major component of tendons and ligamentsCollagen - strong and flexible but resist stretchingElastin - thin with high degree of elasticity ability to stretch and recoilStress / Strain curvesFig 54.1 ACSMLinear - elastic region - will return to original shapenon linear - plastic deformation and repair by fibroblastsSustained stretch of 30-90 seconds in necessary to get beyond elastic recoil properties of skeletal muscle and stimulate fiber reorganizationGoal of flexibility training program is to induce gradual deformation of connective tissue - stimulate repair and greater ROM

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14. 14Limits due to Connective TissueAging Joints become less stable and less mobileDegradation of collagen, joint surface, and decreased viscosity of synovial fluidincreases collagens diameter and more collagen cross-linksStiffness and inflexibility common with agingSometimes difficult to separate aging from wear and tear to jointsFlexibility training can induce remarkable improvements in aged population if no permanent damage to joint structure has occurred

15. 15Assessment of FlexibilityMeasurement made visually or with special instrumentationUtilize active or passive movement of subjectPrecision in assessment techniques enhances both accuracy and reliabilityProper identification of landmarksConsistency in the inclusion or exclusion of a warm-up is important for reliabilityStarting position and body position for measurementsVisual assessment (qualitative) - inaccurate for both spinal and extremity evaluation but useful for fitness screening, group evaluation and field testing - we will do several visual assessmentsDegree of completion of assessment in standard position - see lab manual Eg - Finger tips touching (or not) with combined bilateral rotation of shoulders and elbow flexion

16. 16Quantitative Assessment of FlexibilityMeasurement DevicesIndirect - linear - sit and reach apparatus, anthropometer, tape measureDirect - ROM in degrees - Goniometer / Leighton FlexometerGoniometer is inexpensive and portableKin 142 no longer uses FlexometerWe will perform one measurement with Flexometer for familiarity and one with Goniometer for reviewDynamic Flexibility can be measured with stop motion video with reflective markers on bony landmarks Similar to motion capture for video games and animation

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18. 18Quantitative MeasurementsEg. Sit-reach (modified by Hoeger) - accounts for influence of length of body segments necessary when doing indirect measuresFirst measure taken with back touching wallSecond measurement with truck flexionDifference provides data for comparison

19. 19Benefits of Flexibility TrainingIncreased physical performance Decreased risk of injury (but not due to inclusion as part of a warm-up)Increased blood supply and nutrients to joint structureIncreased quality and quantity of joint synovial fluidIncreased muscular coordinationImproved muscular balance, posture and postural awarenessDecreased muscle viscosity, causing contractions to be easier and smoother

20. 20Benefits of Flexibility (cont)Reduced muscular sorenessPromotion of relaxation (reduced muscular tension and cramps)Decreased risk of low back painReduced stress and tensionIncreased enjoymentPromotes self-disciplineUnification of body, mind and spirit (e.g. Yoga)Improves ease and efficiency of movementIncreased Range of MotionImproves skill in sport

21. 21Reasons why stretching before exercise may not prevent injuryAn increase in muscle compliance may cause tissues to rupture more easily.Stretching before exercise will have no effect for activities where excessive muscle length is not an issue.Stretching will not affect muscle compliance during eccentric activity, where most strains are believed to occur.Stretching can produce damage at the cytoskeleton level.Stretching appears to mask muscle pain in humans.

22. 22Who should not Stretch?Everyone can learn to stretchCaution for people who have naturally excessive ROM - should not stretch in extremes of ROM as joint stability should be maintained Recent push to certify Yoga instructors locally, reduce incidence of injury to clientsPregnancy - hormone Relaxin - softens ligaments and connective tissue especially in pelvis - excessive stretching can lead to hypermobility of low backTable 54.2, 54.3 ACSM

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25. 25Flexibility Training ProgramAthletes should stretch following practice or as a separate session (after sufficient warm up)Muscle is warm, collagen is elastic which allow greater stretch May decrease muscle sorenessTraining ProgramA planned, deliberate, and regular program of exercises that can permanently and progressively increase the useable range of motion of a joint or set of joints over a period of time (Corbin and Noble, 1980).Stretching recommended after sitting or standing for long periods - helps prevents discomfort (not enough to count as a training program)

26. 26Duration and FrequencyVariable opinionsDurationBeaulieu - 10-15 secs - progress to 45-60 secs over 4-5 weeksAnderson - 10-30 sec easy; 10-30 sec developmental stretchACSM 10-30 seconds - but emphasize that connective tissue deformation and neuro-inhibitory effects require 30-90 seconds to effect tissue change and relaxationYoga - variable - 45-90 secondsFrequencyBeaulieu - 2-3 times / weekYoga - daily for 30-45 minutes - relaxation

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28. 28ControversyOptimum flexibility sport specific?Types of stretchingSafety vs effectivenessStatic vs dynamic stretching and performanceDangerous stretchesCautions in some guides, recommended in others?Stretching during warm-up and cool-downIs it enough to effect changes in flexibility?Does it have an impact on injury or muscle soreness?

29. 29Ballistic Stretching(bouncing)AdvantagesDevelopment of dynamic flexibilityEffectivenessTeam camaraderieInterestDisadvantagesInadequate tissue adaptationSoreness and injuryInitiation of stretch reflexInadequate neurological adaptationDisadvantages outweigh advantages

30. 30Static Stretching AdvantagesHistorical preferenceEffective and optimalDecrease possibility of exceeding normal ROMLess energyLess muscle sorenessRecommended as advantages outweigh disadvantages - especially for general population DisadvantagesBoringMay overly dominate routine due to time neededAllows body to cool during warm upPrinciple of specificity - effectiveness for improving dynamic flexibility?Increase chance of injury by reducing amplitude of stretch reflex?

31. 31Dynamic Stretching(mobility drills)AdvantagesFocused on sport specific movementDevelopment of dynamic flexibilityIncreases temperatureMuscle is activeTeam camaraderieInterestAvoids bouncing and is more controlled than ballistic stretchingDisadvantagesInadequate tissue adaptation (ROM)Soreness after first sessionsInadequate neurological adaptationadvantages outweigh disadvantagesNSCA - Essentials of Strength Training and Conditioning 2008

32. 32Dynamic Stretching(mobility drills)Preferred method of stretching during warm upActively moving joint through ROM required for sportObserve sport specific movement patterns, and select exercises that mimic those patternsBuild progressively through each exerciseSpeed and ROMPerform under controlROM often less than what could be achieved with ballistic type movementsDo not accelerate limb to end of ROMNSCA - Essentials of Strength Training and Conditioning 2008

33. 33Dynamic StretchingSTRAIGHT-LEG MARCH(for the hamstrings and gluteus muscles)Kick one leg straight out in front of you, with your toes flexed toward the sky. Reach your opposite arm to the upturned toes. Drop the leg and repeat with the opposite limbs. Continue the sequence for at least six or seven repetitions.

34. 34SCORPION(for the lower back, hip flexors and gluteus muscles)Lie on your stomach, with your arms outstretched and your feet flexed so that only your toes are touching the ground. Kick your right foot toward your left arm, then kick your leftfoot toward your right arm. Since this is an advanced exercise, begin slowly, and repeat up to 12 times.Dynamic Stretching

35. 35HANDWALKS(for the shoulders, core muscles, and hamstrings)Stand straight, with your legs together. Bend over until both hands are flat on the ground. “Walk” with your hands forward until your back is almost extended. Keeping your legs straight, inch your feet toward your hands, then walk your hands forward again. Repeat five or six times. G.R. Dynamic Stretching

36. 36NSCA - Essentials of Strength Training and Conditioning 2008

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38. 38Additional ClassificationsPassive stretching - partner or stretching machine provides external forceActive Stretching - person stretching provides forceProprioceptive Neuromuscular Facilitationcontract muscle prior to stretch- 6 sec contraction; 10-30 sec stretch (Contract - Relax)Autogenic inhibitionGolgi tendon organ and muscle spindle relaxationSome also coincide stretch with contraction of agonist (ms opposite one being stretched) (Contract - Relax (Agonist Contract))Reciprocal inhibitionIncreased range of motion over static stretchingMore motivation required - beneficial to have knowledgeable partnerMore timeIncrease pain and soreness and injury?

39. 39NSCA - Essentials of Strength Training and Conditioning 2008