Stretching is a subject that evokes much debate, when to stretch, for how long and how are questions that often arise. There are three main types of stretching commonly used static/passive, pre contraction and dynamic. What type of stretching is best is dependent on many variables.
Static stretching is when a muscle is put into a position of stretch and then held. If this type of stretch is performed by a third party taking the weight of the limb and placing the muscle on stretch then this is referred to as a passive stretch, the type that might be performed by a clinician. Some research has suggested that if a static stretch is held for greater then 30 seconds no greater range of movement will be accomplished? Regardless of how long a static stretch is held, I personally would be more concerned about how the stretch was performed. During all stretching it is imperative that attention is paid to the position of the origin and insertion of the muscle as well as any compensatory movements elsewhere in the body and that if necessary props or supports are used to allow the body to settle into the desired stretch.
Over the last decade research has told us that static stretching prior to a dynamic movement like sprinting can be detrimental to an individuals performance as it has been found to reduce explosive muscular power, with some studies indicating that static stretching prior to such an activity is more detrimental then not stretching at all. The general advice for sports is to warm up the body using gentle dynamic movements mimicking the activity that is about to take place.
Pre contraction stretching is when a muscle is contracted prior to the stretch being applied. This is also sometimes referred to as proprioceptive neuromuscular facilitation (PNF) or hold relax. Like all stretching techniques there are varying suggestions of what works best, you can hold the contraction for anything between 3 – 10 seconds at a maximal voluntary contraction (MVC) of 20 – 100%. Personally, if I use this type of stretching as part of a rehab programme I tend to steer towards the lower MVC range of about 25% at 6 -10 seconds hold with up to 3 repetitions.
Dynamic stretching can come in two forms active and ballistic. Active dynamic stretching involves taking the muscle through its full range gradually, taking into consideration the dynamic forces through the rest of the body. Ballistic involves rapid movements often with end of range bouncing, this is generally considered a high risk type of stretch open to high injury rates due to the sudden aggressive nature of the stretch.
My preferred mode of stretch is the active dynamic approach encouraging the awareness of the base of support and the line of movement to its end point, gradually increasing the range as the body naturally gives to the resistance encouraging stability in the movement as well as length. Many of the movements that we perform in pilates could be deemed as dynamic stretching.
So should we stretch after physical activity? As a Physiotherapist & Pilates teacher I see first hand the results of what repetitive movements can do to a bodies function. For example if an individual sits all day at work all day and then runs regularly during the week, you may see a gradual shortening of the pectorals and hip flexors as both activities favour a flexion bias of movement. To prevent these imbalances developing its imperative that the joints and soft tissues are moved in a variety of different movement patterns at different times during the day.
Most people would probably agree that some form of stretching in our daily routines definitely helps to prevent muscle imbalances and joint stiffness from occurring, but ultimately educating the individual to be more mindful and postural aware of their daily movements should be our first priority. This to me this is where Pilates fits in perfectly as the movement education link between functional daily movements, leisure activities and injury prevention.
How to use stretching and its benefits can be validated by research but ultimately we need to look at the individual and consider their body type, daily activities, medical history, age and much more. So keep an open mind do some independent research and find the best method that suits you and your specific client, not one size fits all!