The Navy SEAL Physical Fitness Guide 113
There is some controversy surrounding the effectiveness of dynamic stretching and
its role in the development of flexibility. Some experts believe that the short, intermittent
movements involved in this type of stretching activate the stretch reflex and cause the
stretched muscle to contract. Others maintain that dynamic stretching is beneficial for
quick, explosive activities like gymnastics or martial arts. However, in general, dynamic
stretching should not be used to develop static flexibility or long-standing changes in range
of motion. If used at all, dynamic stretching functions best before exercise to enhance
performance. This type of stretch is often performed after a warm up and prior to an
exercise session in anticipation of a particular activity. Dynamic stretches should mimic the
activity that is to be performed.
Static Stretching
Static stretching (sometimes referred to as passive stretching) develops static
flexibility and uses slow, controlled movements through a full range of motion. This type
of stretch is performed by holding a position using a part of the body, the assistance of a
partner, or some other apparatus such as a pole or the floor (e.g., lifting one leg up and
holding it with the hand, the splits). Slow, static stretching helps relieve muscle spasms due
to exercise, and is used for cooling down after a workout to reduce muscle fatigue and
soreness.
Ballistic Stretching
Ballistic stretching uses the momentum of the body or a limb to force a stretch past
the normal range of motion and then return to the starting position. Ballistic stretching
incorporates bouncing or jerky movements and should not be confused with dynamic
stretching. An example of a ballistic stretch would be bouncing down to touch toes or using
the momentum of the torso to twist the body. Uncontrolled arms swings in which the arms
are thrown backward and then bounce back to the starting position are also an example.
This type of stretching does not contribute to flexibility. Instead, the repeated activation of
the stretch reflex causes muscles to contract which can lead to injury. This type of
stretching is not recommended.
PNF Stretching
Proprioceptive neuromuscular facilitation (PNF) stretching is considered an
advanced stretching technique. It is used extensively by physical therapists or when high
degrees of both passive and dynamic flexibility are required for performance (e.g., martial
arts, ballet, gymnastics, kick-boxing). There are several PNF techniques, but generally,
PNF consists of a passive stretch, followed by an isometric contraction, which is then
followed by another stretch (static or dynamic). By combining passive stretching with
isometric contractions (a contraction in which there is no change in muscle length or joint
movement) with a partner or object for resistance, PNF uses the stretch reflex and
lengthening reaction to achieve a greater range of motion. As described in the section