FlexibilityFlexibility

KIN 325KIN 325

1. 1. DefinitionDefinition

The range of motion that can be elicited The range of motion that can be elicited at a particular joint or group of jointsat a particular joint or group of joints

Range of motion is highly specific; it Range of motion is highly specific; it differs between jointsdiffers between joints

Also varies between people due to:Also varies between people due to:

• genetics and gendergenetics and gender• physical activity levelphysical activity level• joint structurejoint structure

• ageage• tissue injurytissue injury• adipose tissueadipose tissue• body temperaturebody temperature

2. 2. The benefits of a flexibility training programThe benefits of a flexibility training program

• Maintain good joint mobility, allowing forMaintain good joint mobility, allowing for

proper body mechanicsproper body mechanics• Reduce mechanical stress within the jointsReduce mechanical stress within the joints• Muscular relaxationMuscular relaxation• Relief of muscular crampsRelief of muscular cramps• Increase resistance to muscle injury Increase resistance to muscle injury • Improve and maintain good postural alignmentImprove and maintain good postural alignment• Prevent low-back and other spinal column problemsPrevent low-back and other spinal column problems

3. 3. Connective Tissue: a limiting factor forConnective Tissue: a limiting factor for flexibilityflexibility

Joint capsule and associated ligaments contribute Joint capsule and associated ligaments contribute approximately 47% to restriction of ROM; muscles contribute approximately 47% to restriction of ROM; muscles contribute 41%, the tendons 10%, and skin 2%41%, the tendons 10%, and skin 2%

Stretching exercises help to cause minor distensions in Stretching exercises help to cause minor distensions in connective tissue and summation of these small changes can connective tissue and summation of these small changes can improves ROMimproves ROM

Increase in stretch toleranceIncrease in stretch tolerance

4.4. Sensory Receptors Related to StretchingSensory Receptors Related to Stretching

a. a. Muscle spindlesMuscle spindles

Primary stretch receptors in muscle, encased in a spindle-shaped Primary stretch receptors in muscle, encased in a spindle-shaped capsule which is attached at both ends to the muscle fiberscapsule which is attached at both ends to the muscle fibers

b. Golgi tendon organsb. Golgi tendon organs

Located at the muscle-tendon junction, not within the tendon. Located at the muscle-tendon junction, not within the tendon. Main function is to monitor muscle tensionMain function is to monitor muscle tension

5. 5. Stretching methodsStretching methods

a. Ballistic stretchinga. Ballistic stretching

• Associated with bobbing or bouncing. Fast, dynamic stretches.Associated with bobbing or bouncing. Fast, dynamic stretches.

Advantages:Advantages:

• Develops dynamic flexibilityDevelops dynamic flexibility• Permits specificity of training Permits specificity of training

DisadvantagesDisadvantages

• Quick stretch allows little time for adaptation. Permanent Quick stretch allows little time for adaptation. Permanent lengthening is most effectively achieved by lower force, longer lengthening is most effectively achieved by lower force, longer duration stretches duration stretches

• Fast stretches create high tensile forces. Can result in injuryFast stretches create high tensile forces. Can result in injury or muscle sorenessor muscle soreness

• Might elicit the stretch reflex. Causes muscle contraction,Might elicit the stretch reflex. Causes muscle contraction, therefore increases tension. therefore increases tension.

b. Static stretchingb. Static stretching

• a static position held for a period of timea static position held for a period of time

Advantages:Advantages:

• muscle soreness minimizedmuscle soreness minimized• injury risk minimizedinjury risk minimized• more effective than ballistic stretching for increasing more effective than ballistic stretching for increasing

ROMROM

Disadvantages:Disadvantages:

• Not specific to many movements where dynamic Not specific to many movements where dynamic flexibility is requiredflexibility is required

c. c. Proprioceptive Neuromuscular Facilitation (PNF)Proprioceptive Neuromuscular Facilitation (PNF)

Incorporates various combinations of relaxation and Incorporates various combinations of relaxation and contraction periods for the muscles being stretchedcontraction periods for the muscles being stretched

The theory is that a simple reflex, initiated by the Golgi The theory is that a simple reflex, initiated by the Golgi tendon organs during the contraction phase, will cause tendon organs during the contraction phase, will cause the muscle to relax more and offer less resistance to the muscle to relax more and offer less resistance to the stretchthe stretch

Contract-relax method - Contract-relax method - autogenic inhibitionautogenic inhibition

A variation of this method is the contract relax with A variation of this method is the contract relax with

agonist contraction (CRAC) technique – also agonist contraction (CRAC) technique – also incorporates incorporates reciprocal inhibitionreciprocal inhibition

Advantages:Advantages:

Most research shows this method produces the largest gains Most research shows this method produces the largest gains in flexibilityin flexibility

Also develops strength in the muscle as large forces are Also develops strength in the muscle as large forces are developed when the muscle is isometrically contracted in developed when the muscle is isometrically contracted in stretched positionstretched position

DisadvantagesDisadvantages

Elicits the most discomfortElicits the most discomfort DOMS can resultDOMS can result Greater risk of injury than with static stretchingGreater risk of injury than with static stretching Usually requires a partnerUsually requires a partner Not recommended for patients with CVD, as blood pressure Not recommended for patients with CVD, as blood pressure

might rise too highmight rise too high

6. Exercise Prescription6. Exercise Prescription

Mode: static or PNFMode: static or PNF

Frequency: at least 3 days per weekFrequency: at least 3 days per week

Intensity: to point of discomfort, not painIntensity: to point of discomfort, not pain

Duration: 10 to 30 seconds each stretchDuration: 10 to 30 seconds each stretch

Repetition: 3 to 5 for each stretchRepetition: 3 to 5 for each stretch