This is an excerpt from Full-Body Flexibility-2nd Edition by Jay Blahnik.
Stretching Techniques and Terms
First let's review a few important techniques and terms. Even if you're familiar with stretching, it's a good idea to double-check your knowledge of this information. Some of these terms are commonly confused and misused.
Static stretching means a stretch is held in a challenging but comfortable position for a period of time, usually somewhere between 10 to 30 seconds. Static stretching is the most common form of stretching found in general fitness and is considered safe and effective for improving overall flexibility. However, many experts consider static stretching much less beneficial than dynamic stretching for improving range of motion for functional movement, including sports and activities for daily living.
Dynamic stretching means a stretch is performed by moving through a challenging but comfortable range of motion repeatedly, usually 10 to 12 times. Although dynamic stretching requires more thoughtful coordination than static stretching (because of the movement involved), it is gaining favor among athletes, coaches, trainers, and physical therapists because of its apparent benefits in improving functional range of motion and mobility in sports and activities for daily living.
Note that dynamic stretching should not be confused with old-fashioned ballistic stretching (remember the bouncing toe touches from PE classes?). Dynamic stretching is controlled, smooth, and deliberate, whereas ballistic stretching is uncontrolled, erratic, and jerky. Although there are unique benefits to ballistic stretches, they should be done only under the supervision of a professional because, for most people, the risks of ballistic stretching far outweigh the benefits.
Passive stretching means you're using some sort of outside assistance to help you achieve a stretch. This assistance could be your body weight, a strap, leverage, gravity, another person, or a stretching device. With passive stretching, you relax the muscle you're trying to stretch and rely on the external force to hold you in place. You don't usually have to work very hard to do a passive stretch, but there is always the risk that the external force will be stronger than you are flexible, which could cause injury.
Active stretching means you're stretching a muscle by actively contracting the muscle in opposition to the one you're stretching. You do not use your body weight, a strap, leverage, gravity, another person, or a stretching device. With active stretching, you relax the muscle you're trying to stretch and rely on the opposing muscle to initiate the stretch. Active stretching can be challenging because of the muscular force required to generate the stretch but is generally considered lower risk because you are controlling the stretch force with your own strength rather than an external force.
Every stretch is static or dynamic and passive or active, as illustrated in the examples shown in table 1.1.
You might hear or read about other techniques and terms used in stretching (especially by coaches and athletes), such as proprioceptive neuromuscular facilitation (PNF) stretching or active isolated stretching. These techniques are all simply variations of these four types of stretches.
Most of the stretches you see and do are likely static-passive stretches. Static-passive stretches are the most common stretches and the easiest to perform. If executed with good technique, these stretches are effective in improving flexibility and range of motion.
However, most experts now agree that although static-passive stretches have many benefits, it's best to do more dynamic-activestretches. Because dynamic-active stretches require you to use and build your own strength while moving through the stretch, they are more helpful for improving functional movements used in everyday life and in sports. In addition, because dynamic-active stretches are movement oriented, these stretches can help generate heat, which can make the muscles more pliable. Finally, evidence suggests that because dynamic-active stretches require muscle activation and contraction, the muscles being stretched are triggered to relax even more than they might during a static-passive stretch, thereby reducing the risk of injury while increasing the functional benefit.
This does not mean you should avoid or minimize static-passive stretching. Just be aware that there appear to be quite a few advantages and benefits to dynamic-active stretching and that you should include these types of stretches as often as is comfortably and conveniently possible for you.
Read more about Full-Body Flexibility, Second Edition.