The Basics Of Flexibility

Flexibility is defined by the ACSM (2013), as the “ability to move a joint through its complete ROM” (ACSM 2013). ROM or range of motion is the complete mobility possible (Fahey et al., 2020). Flexibility is specific to each joint, meaning that stretching, and improving flexibility in one joint, won’t translate to another joint. Which is why a full body flexibility program is important in order to get ideal ROM at all your major joints. According to the ACSM (2013) the flexibility of each joint will depend on both the stretchability and distensibility of the joint capsule itself, how warm the associated muscles are, the viscosity of the muscle, as well as the tightness of the tissues, ligaments, and tendons associated with the joint. Other factors that influence flexibility include age, physical activity level, sex, previous injuries, and genetics (Porcari et al. 2015).

Why is Good Flexibility Important

Adequate flexibility is important for many reasons. For starters, poor flexibility can lead to poor joint health by putting too much stress on the joint, leading to issues like joint deterioration and joint pain (Fahey et al. 2020). Adequate joint ROM is important for athletics, maintaining ADLs (ACSM 2013), preventing arthritis, maintaining or improving stability and balance, prevention of low back pain, relief of some aches and pains, relief of muscle cramps, improvement in body position and postures, relaxation, and potentially improvement in impaired mobility (Fahey et al., 2020). It likely does not come as a surprise that a low level of flexibility increases one’s risk of injury, but it is also important to note that having an overly high level of flexibility can also increase injury risk due to decreased joint stability. The term hypermobile is used to describe someone who has a greater than normal ROM, while hypomobile could be used to describe someone with below normal levels of ROM (Porcari et al. 2015).

Stretching

Participation in a regular and consistent stretching program (at least 2-3 times a week) will improve flexibility. Some transient ROM improvements can be seen immediately after stretching, while chronic improvement can be noted in as little as 3-4 weeks (ACSM 2013) .

Types Of Stretching

One of the most prescribed forms of stretching is static stretching. This form of stretching is commonly recommended because it is both effective, safe, and easy to do (Fahey et al. 2020). Static stretching is stretching to an end point and holding (ACSM 2013). A single static stretch is typically held for 10-30 seconds per stretch The stretch should be felt, but should not be painful.

Another form of stretching is dynamic stretching. Dynamic stretching is moving a joint through its ROM during the stretch. It is important to note that with dynamic stretching the movement is slow and controlled, and often exaggerated (Fahey et al. 2020). Dynamic stretching differs from static stretching in that instead of stretching to an end point and holding the stretch, you are in motion with the goal of increasing the ROM covered in that motion with each movement. Dynamic stretching is safe and effective but requires more coordination and balance.

A less commonly prescribed type of stretching is ballistic stretching. Ballistic stretching uses a bouncing motion to create a force behind the stretch (Fahey et al. 2020). Ballistic stretching has an increased likelihood of injury and thus is not a commonly recommended form of stretching for the general population. According to ACSM (2013) when properly performed, ballistic stretching may be an effective choice for individuals who participate in sports and activities that utilize ballistic movements.

Another type of stretching is proprioceptive neuromuscular facilitation (PNF) . The most common form of this is a contract relax type of stretching. PNF stretching typically involves the assistance of another person. With PNF stretching there is typically an isometric contraction (muscle contraction without a change in muscle length) phase, followed by a static stretch phase (ACSM, 2013). The contract phase can then be repeated followed by another stretch phase. During the second stretch phase the individual is likely able to stretch further. There are variations of PNF stretching. See the video linked below for an example of PNF stretching.

Recommendations

It is important that muscles are warm prior to beginning a stretching session. If you are only going to be stretching and not doing other forms of physical activity, begin with a warm up. A warm up will raise the temperature of the muscles and increase blood flow. If you are participating in other forms of exercise or physical activity, it is recommended that you stretch immediately after your cool down, while your muscles are still warm. According to the ACSM (2013), flexibility exercises should be performed after exercise because there may be a possibility that stretching can decrease power and strength for a short time period after the stretching session. By completing stretching after other forms of exercise, this is not an issue.

Stretching should be performed at least 2-3 times per week, but it is ideal to stretch more often. Stretching up to 7 days a week is safe (Fahey et al., 2020). Stretching should target major muscle-tendon units and ideally be repeated 2 to 4 times (Porcari et al., 2015).

Any of the above stretching techniques (see Types Of Stretching ) can be used, but ballistic stretching is not ideal for everyone. Dynamic stretching can also be challenging for individuals who lack balance and coordination. The most common stretching for most individuals is static stretching. With static stretching, it is recommended that each stretch is held for 10-30 seconds (or 30 -60 seconds in older adults) and repeated 2-3 times (ACSM 2013). The goal is to have a total of 60 seconds of combined stretching.

Use the link below to find a beginner’s guide to static stretching by NASM (National Academy of Sports Medicine).

Stretches for Beginners: 10 of the Best Movements for Those Just Starting