6.4. Flexibility Flashcards
Definition
The range of motion around a joint
Why is flexibility important?
- Reduced injury risk
- Improved posture and alignment
- Reduction in DOMs, due to less muscle damage
- Improves ROM
Static flexibility:
The range of motion around a joint in a still position
Types of static flexibility
- Static active
- Static passive
Static active flexibility
When the performer themselves moves a joint to the point off resistance
Static passive flexibility
When a joint is moved to the point of resistance with assistance
Dynamic flexibility
The range of motion around a joint moving at speed
Factors affecting flexibility
- Type of joint
- Joint shape
- Length/ elasticity of muscles/ connective tissue
- Gender
- Age
How does joint type affect flexibility?
Joint type determines number of movements a joint can produce
How does joint shape affect flexibility?
A shallow joint has more ROM compared to deeper joint
How does length of surrounding connective tissue affect flexibility
The longer the length of the surrounding tissue, such as ligaments, tendons and muscles, the greater the ROM
How does gender affect flexibility?
Females tend to have greater flexibility than males due to higher levels of oestrogen and relaxin.
These hormones increase connective tissue elasticity.
How does age affect flexibility?
Flexibility is greatest in childhood and declines with age as elasticity in surrounding connective tissue is lost.
Sit and reach test:
- Sit and reach box used
- Performer puts socked feet up against front of box and with straight legs, leans forward to reach as far along the top of the box as possible.
- The position must be held for 2 seconds.
- Score can be read from box top and compared to standardised tables.
Strengths of sit and reach
- Relatively cheap equipment
- Test is easy to administer
- Standardised tables available
Limitations of sit and reach test
- Only measures static flexibility in lower back and hip joints
- Performer must warm up and not safe to use at speed
Goniometry
- Put the goniometer at centre of joint and put the end on the articulating limbs
- Measure the start and end angles and compare the diffs
- Score is diff between two
Strengths of goniometry
- Can be used to measure flexibility of any joint
- Valid and accurate measurements
Limitations of goniometry
- Can be difficult to locate joint centre
- Test is unreliable and invalid if correct procedure not followed
Active stretching training
- Unassisted voluntary static contraction of an agonist muscle to stretch connective tissue in agonist just beyond point of resistance.
- Position held using strength of agonist muscle
- Held for 10 secs
Passive stretching training
- Taking joint just past point of resistance with assistance from partner or stretching aid.
- Stretching aid can be a diff body part, exercise band or gravity
- Held for up to 30 secs
Isometric stretching
- Passive stretch performed
- Stretched muscle undergoes isometric contraction for 10 secs
- Resistance needed to ensure no movement takes place
- Muscle relaxed for at least 20 secs
PNF stretching
- Passive stretch
- Agonist isometrically contracts against resistance for 10 secs
- Relax and repeat passive stretch - second stretch will be further than first
- When muscle is stretched, muscle spindle is activated and muscle contracts
- When muscle contracts, golgi tendon organ is activated and muscle relaxes
- It’s believed that if a stretch is initiated straight after a contraction, the muscle spindle is briefly overridden and golgi tendon is activated allowing a deeper stretch.
Muscle spindle apparatus
- Small complex spindle shaped proprioceptor found in skeletal muscle
- Nervous system is stimulated when length of relaxed muscle is stretched and exceeds certain limit
Triggers response via efferent nerve - initiates reflexive muscle action, thus shortening the muscle - Plyometric training uses this stretch reflex to facilitate the recruitment of additional motor units
- Stretching attempts to overcome the stretch reflex and reduces its sensitivity to stimulation.
Golgi tendon organs
- Stretch receptors located between a muscle and tendon
- Work in opposite manner to muscle spindle, when activated golgi organs cause muscle to relax which protects muscle from tearing
- Require strong stretches before activated.
- PNF uses this part of process to develop flexibility.
Dynamic stretching training
- Using a controlled movement, bounce or swinging motion to take a joint to the limit of its range of motion
Ballistic stretching
- Incorporates vigorous swinging or bouncing movements, thus using momentum to move a joint forcibly through its extreme ROM
Physiological adaptations to flexibility training
- Increased resting length of muscle and soft tissue
- Increased elasticity of muscle and soft tissue
Increased resting length of muscle and soft tissue
- Muscle spindles adapt to new resting length, delaying stretch reflex
- Effectiveness or aesthetic sports/ techniques increases
Increased elasticity of muscle and soft tissue
- Increased ROM leads to more efficient movement and force generation
- Risk of injury decreased
- Increased effectiveness or aesthetics of performance
Strengths of static (active/ passive) stretching
- Simple
- Effective increasing ROM
- Aids muscle relaxation post exercise
Weaknesses of static (active/ passive) stretching
- Doesn’t prepare muscles for dynamic movements
- Slow method of increasing ROM
- May decrease power after stretch (research suggests it should be avoided before exercise)
Strengths of isometric stretching
- Overcomes the stretch reflex for a deeper stretch
- Increases static flexibility in a more painless way
Weaknesses of isometric stretching
- Risk of damaging tendons- therefore should not be done by U16s
- Only perform once every 6 hrs
Strengths of dynamic stretching
- Improves specific game related movements
- Less chance of injury
- Improves speed and power following stretches
Weaknesses of dynamic stretching
- Does not assist with muscle relaxation after exercise
Strengths of ballistic stretching
- Improves speed and power
- Best suited to pre-exercise
Weaknesses of ballistic stretching
- Limited for development of ROM
- Greater risk of injury
Strengths of PNF
- Quickest way to develop ROM
- Appropriate for joints with poor ROM
Weaknesses of PNF
- Complex
- Requires partner
- More discomfort than static
