Stretching is a common activity associated with physical fitness. Most people have an idea that they “should” stretch – perhaps as part of a warm-up routine prior to more intense physical activity, or in order to stay generally flexible in the joints. Many people are also aware that over the last 10-20 years, the recommended method of stretching has shifted. Do you recall when you were first told “not to bounce” when in a stretch position? Currently, you may have heard different terms such as “Assisted Stretching” or “Dynamic Warm-up” being utilized in the fitness community. You may see your kids or adults in group exercise classes doing different things before and/or after their workouts than you recall doing when you were first participating in sports. Or you may see an absence of anything that looks like “stretching” in these same activity environments. It would be understandable to be a bit baffled about what you should or should not be doing in association with your own physical fitness. Read on for a bit of a lesson about the potential benefits and limitations of stretching.
The basic reason for stretching is to increase range of motion (ROM). Human activity is dependent on the ability of the musculoskeletal system to move around. Both the joints that serve as connections between your bones and the muscles that attach near the joints and which contract and/or relax to create movement in the body are potentially affected by stretching. Additionally, the nerves that talk to your joints and muscles also are involved in allowing (or restricting) movement. Each of these tissue types – bone, muscle, and nerve – have different physical qualities and therefore respond differently to force. When considering this, it makes sense that there might be confusion about how “best” to stretch. Really, the “best” means of improving range of motion totally depends on why motion is limited. And limitations will exist in different bodies for different reasons.
In the interest of keeping this lesson reasonably short, we will omit a larger discussion of why different tissue types respond to different forces, and why a physical therapist or other exercise prescribing professional like a coach or an athletic trainer might prescribe different things to different people. An optimally prescribed stretching program would take into consideration each individual human’s particular musculoskeletal health and functional status. This determination is part of what we do at Symmetry when we evaluate each patient when things are not working correctly in order to design a personalized treatment program aimed at recovery of optimal physical performance. For the moment, we will instead focus on some general universally applicable guidelines based on the physical therapy research that is most current at the moment.
Here are some good reasons to incorporate stretching into your general fitness routine:
- Stretching increases range of movement and flexibility.
- Increased range of movement can help joints and muscles work effectively
- Increased flexibility may reduce injury risk
Here is a summary of the most common types of stretching:
- Static Stretching – a type of stretching that involves the gradual lengthening of muscle by maintaining a low force on tissue over a relatively long period of time. This type of stretching lengthens muscle, decreases musculotendinous stiffness, and often increased joint range of movement.
- Dynamic Stretching – a type of stretching that involves controlled movement through an available range of movement, often with progressively larger movement throughout the stretching interval. This type of stretching improves motor control and increases tissue temperature as well as enabling increased joint and muscle movement.
- Assisted Stretching / Pre-Contraction Stretching – a type of stretching that typically involves a muscle contraction (tightening) prior to a stretch. Often, a partner is assisting the person stretching by providing resistance that creates a contraction and then helps to move the muscle to a maximally lengthened position. (It is possible in many cases, however, to accomplish this type of stretching without another person’s assistance.) Pre-contraction stretching increases range move movement by creating reflexive relaxation in a muscle after the stimulation of the tightening contraction.
Then, here are some generalizations for why or when you might use each type of stretch:
- Static stretching is effective at increasing range of movement. Typically, 2-4 repetitions of any given stretch, with a hold time of 10-30 seconds, create this flexibility effect. In some cases – particularly in older persons – longer hold times may work better to produce a change in ROM.
- The “down” side of static stretching is that in the immediate aftermath of a static stretch, muscle strength and performance has been found to diminish. Because of this phenomenon, the popular use of static stretching BEFORE athletic endeavors is steadily decreasing.
- Dynamic stretching is an effective part of a pre-sports warm-up. The increased tissue temperature and more efficient motor control of joints and muscles that occur after this type of stretching makes it a good choice for use prior to athletic activity – particularly for sports that require intricate movement patterns, high speeds, or lots of muscular power.
- Assisted / Pre-Contraction stretching has been found to result in quick and immediate gains in motion. However, as with static stretching, there appears to be an associated decrease in muscle strength immediately after this type of stretch. This sort of stretching is likely to work well in a training or rehabilitation environment when improved mobility is needed to then allow proper practice of a movement pattern that is being developed or modified.
What does research say about the effectiveness of stretching?
- According to a position paper published by the American College of Sports Medicine, some form of stretching is recommended as a part of a well-rounded general exercise routine. Any of the stretching types can help people to attain and/or maintain good range of movement in all of their joints and muscles, which can help the body to function efficiently during typical daily tasks.
- Research is mixed about whether or not stretching can help to prevent injury. Some evidence suggests that participation in dynamic stretching warm-up routines is associated with decreased incidences of injury in particular populations of sports participants. For example, both youth and adult soccer players appear to have fewer hamstring injuries when they regularly participate in a fairly extensive dynamic stretching routine prior to play. An analysis of stretching by the National Institutes of Health suggests that more research is needed to determine if stretching alone can reduce muscular injuries. It is likely that injury prevention is more comprehensively addressed by using stretching as one component of a broader plan for optimizing sports performance that also includes things like strength and balance training.
- Stretching in a variety of forms appears to be a useful component in successful rehabilitation programs for a variety of orthopedic conditions. As mentioned previously, the best outcome for any particular person is likely related to optimal and individualized prescription of stretching parameters.
We hope that this summary provides a useful guideline about the benefits and limitations of stretching. If you have questions about how stretching might benefit you, feel free to contact the team at Symmetry. We’d be glad to be a resource for further information.