A conventional definition of flexibility is the range of motion available at a particular joint while the body is at rest. But during activity or competition this is not relevant, since the athletes body is not at rest. Instead flexibility during movement must be reviewed as a dynamic controlled quality: it allows the joint to go through as large a range of motion as can be controlled. The controlling nature of flexibility involves the range of motion used in skill performance and the length of the movement available for force production /reproduction.
The opposite of dynamic flexibility would be instability: which is any degree of mobility that cannot be controlled.

Flexibility for sports is more than maximal lengthening of soft tissue; it is not a posed static position. It is about movement and control of multiple positions that must occur rapidly to meet the demands of an athlete’s sport.
Sport-specific flexibility requires an integrated expression of joint stability, strength, movement awareness and soft tissue extensibility.
Dynamic range of movement expressed in sports movement is significantly greater than can be expressed statically. This is due to the elasticity of the involved tissue and reciprocal inhibition, which allows the opposing muscle to relax. This is why a pitcher can externally rotate beyond 90° when pitching but statically may not be able to get within 10-15° of that dynamic range!
Quote: “While there is no proven connection between joint looseness and overall athletic performance, too much looseness can be a real liability in sports that require rapid changes of direction and acceleration, such as basketball, tennis and soccer, while too little of it would seriously restrict a gymnast or figure skater; and so the quality of joint looseness is largely sport specific.”
(Arnot & Gains, 1984).

It is important to assess flexibility through observing the athletes in their respective sports. Is the athlete smooth in his/her movement, can he/she get in the required positions dynamically? Has there been a pattern of injury?
More detailed functional assessment should be dynamic and intra-individual!
Results are highly individual and therefore should NOT compare flexibility norms. It is a mistake to have norms set that make inter-individual comparisons on this highly individual physical quality.

Now what does this mean for rehabilitation and our patients/clients? They should be allowed the same intra-individual flexibility assessment. Do they functionally require a SLR past 60°?! We should not use the standardization of norms set in a “laboratory setting” to justify continued stretching/mobilization in order to achieve a pre-determined range.

Too many people still equate stretching with warming up. However, stretching is NOT the same as warming up. As a matter of fact, you would have to warm up in order to effectively stretch and gain flexibility.
Static stretching before warming up or competition can lead to fatigue and decrease in coordination, leading to possible injury. It is not logical to use static stretching to prepare for dynamic action.

The optimum time to develop flexibility is post workout! The proper way to warm up is to engage in sport-specific movements or conditioning while gradually increasing the intensity level. This could include 5-10’ of jogging, 10-15’ of dynamic stretching followed by 10-15’ general and sport specific drills.

Dynamic stretching must include multisegmental and tri-planar movements against gravity with neural excitation.
For example with running: stretching must include joint movement even when the muscle is lengthened because that is how they function during running activity: muscles are stretched to provide eccentric segmental stabilization long enough for forward momentum and concentric muscle action to create segmental mobility elsewhere in the body.

To go back to the question posed at the beginning of this article: “Is stretching beneficial in preventing injury and does stretching improve flexibility and performance?”
Stretching can be beneficial in preventing injury if done properly. It should be done dynamically and sport or activity specific.
Stretching is more than just “warming up” and vice versa, warming up is more than just stretching.
It is important to relay this message to clients, patients and athletes alike. Being able to touch your toes does not make you “stiff or flexible”. Spending 10 minutes performing static stretches prior to a work out does not warm you up nor will it prevent injuries from occurring.
Flexibility is more than just loose or long muscles. It incorporates strength, coordination, balance and dynamic stability.
Ultimately it is about control: the ability to control an action or activity will significantly reduce injury and improve performance.