Introduction

Recent research has clearly shown that physical activity is one of the most important factors related to maintaining good health

(Corbin & Pangrazi, 1993; USDHHS, 1996). Programmed physical activity (exercise) and sport are forms of human movement

often used to achieve these positive health benefits. Human movement is not possible without a certain amount of the fitness

component commonly called flexibility. Most exercise and sports programs incorporate activities for flexibility development

because flexibility is thought to be important for safe and effective movement. Stretching exercises provide a training stimulus for

flexibility development. In the following sections we will discuss several topics related to flexibility fitness (1) Definitions of

flexibility, (2) Normal static flexibility, (3) The health-related benefits of flexibility, (4) The performance-related benefits of

flexibility, and (5) Current recommendations for safe and effective development of flexibility

Definitions of Flexibility

One problem in the literature is the inconsistent use of terminology in flexibility, and the related areas of stretching and joint range

of motion. Definitions of key terms are presented in Table 1. Sports medicine professions sometimes use slightly different

terminology than in physical education, sport, and exercise science professions. Common classifications of stretching exercises also

tend to use terminology that conflicts with current biomechanical classifications of flexibility. Even within a discipline there is

potential for confusion in terminology. For example, physical therapists often

distinguish between active range of motion (unassisted) and passive range of motion

(therapist assisted) in assessing static flexibility. Therefore, when reporting a range of

motion for a flexibility test it is important to know whether the test was active or

passive. Flexibility tests can also be confused with the joint laxity tests by which

orthopaedists and athletic trainers evaluate the small accessory rotations and

translations in joints (Corbin, 1984). Additionally, early flexibility research suggested

that there were both static and dynamic expressions of flexibility (Fleishman, 1963),

giving rise to the common use of “static” and “dynamic” modifiers for two kinds of

flexibility (Anderson & Burke, 1991). However, use of these “dynamic” flexibility

tests stopped because they involved ballistic movements that may be more related to

speed, coordination, and strength rather than flexibility.

Flexibility has been defined as “the intrinsic property of body tissues, which

determines the range of motion achievable without injury at a joint or group of joints.”

(Holt et al., 1996: 172). This property of the musculoskeletal system can be examined

by two kinds of biomechanical measurements: static flexibility and dynamic

flexibility (Gleim & McHugh, 1997). Static flexibility is a linear or angular

measurement of the actual limits of motion in a joint or complex of joints. In other

words, static flexibility is a clinical measurement that defines the amount of motion at

a joint or group of joints. There are, however, several complications in the

interpretation of static flexibility measures. First, the limits of the static flexibility

tests are subjectively defined by either the subject or the tester. Physical therapists

usually classify the limits of joint motion according to various “end-feels” e.g. soft,

firm or hard (Norkin & White, 1995). The “end-feel” varies depending on the type of

tissue providing resistance to movement. Generally, static flexibility tests measure

motions limited by the extensibility of the musculotendinous units (MTU)

Series 2, No. 6 July, 1996

President’s Council on Physical Fitness and Sports 

Series 3, No. 10 June 2000

Published quarterly by the 

President’s Council on

Physical Fitness and Sports

Washington, D.C.

★

Guest Authors:

Duane V. Knudson, Ph.D.

Department of Physical Education and

Exercise Science

California State University, Chico

Peter Magnusson, Ph.D.

Team Denmark Test Center, 

Sports Medicine Research Unit, 

Bispebjerg Hospital, 

Copenhagen, Denmark

Malachy McHugh, Ph.D.

Nicholas Institute of Sports Medicine 

and Athletic Trauma, 

Lenox Hill Hospital, New York, NY

★

Co-Edited By:

Drs. Chuck Corbin and Bob Pangrazi

Arizona State University

Current Issues in Flexibility Fitness
2

elasticity implies a higher stiffness, which means the tissue

offers greater resistance (stress) to elongation (strain).

However, for most individuals, greater elasticity implies less

resistance to elongation which is really compliance.

Table 1

Definitions of Key Flexibility Terms

• Anklyosis – Pathologically low joint range of

motion.

• Ballistic Stretching – Fast, momentum-assisted

movements used to stretch muscles.

• Compliance – A material that is easily

elongated with low levels of force is compliant.

Compliance is the opposite of stiffness or

elasticity.

• Dynamic Flexibility – The rate of increase in

tension in relaxed muscle as it is stretched. The

mechanical variable that represents dynamic

flexibility is stiffness. 

• Elasticity – The property of a material to resist

deformation from a force and to quickly return

to its normal shape. The mechanical measure of

a materials elasticity is stiffness. 

• Flexibility – “the intrinsic property of body

tissues which determines the range of motion

achievable without injury at a joint or group of

joints (Holt et al., 1996; 172).”

• Hypermobility – Excessive joint range of

motion.

• PNF (Proprioceptive Neuromuscular

Facilitation) – Specialized stretching routines

that take advantage of reflexes and neuromuscular principles to relax muscles being

stretched.

• Static Flexibility – The measurement of the

range of motion in a joint or group of joints.

• Static Stretching – Slowing elongating a

muscle group and holding it in the stretched

position.

• Stiffness – The measure of a materials

elasticity, defined as the ratio of force to

elongation. 

• Viscoelastic – Complex mechanical behavior

of a material because the resistive force in 

the material is depending on elongation

(elastic) and the rate (viscous) at which the

force is applied. 

surrounding the particular joint or joints. For simplicity, the

term “muscle” will be used in this paper to mean the whole

MTU. The straight leg raise test is a static flexibility test

thought to be limited by the extensibility of the hamstring

muscle group (McHugh et al., 1998). However, ligamentous

constraints and bony congruencies can also limit motions

depending on the joint and the motion being tested. For most

static flexibility tests, the limits of motion are determined by

the subject’s tolerance of the stretched position (Halbertsma

& Goeken, 1994; Magnusson et al., 1996c, 1997) and are

therefore not truly objective measures. Static flexibility

measurements are somewhat limited by the subjective nature

of the assessment of the ends of the range of motion. In

contrast, measures of dynamic flexibility do not depend on

the subjective perceptions of the end of the range of motion,

and therefore, are believed to be more objective measures

(Gleim & McHugh, 1997). Dynamic flexibility refers to the

increase in resistance with muscle elongation for a given

range of motion and can be quantified in terms of stiffness

[see Table 1] (Gleim & McHugh, 1997). So dynamic

flexibility accounts for the resistance to stretch throughout

the range of motion. Tissue stiffness is usually quantified

according to the slope of the load-deformation curve. The

slope of the torque-range of motion curve provides an

equivalent for the in vivo measurement of passive stiffness of

muscle groups (Gajdosik et al 1990, Magnusson et al 1997,

McHugh et al 1998). Dynamic flexibility measurements of

relaxed muscle are important because they essentially tell

how muscle passive tension increases at the limits of the

range of motion, and show that muscle has viscoelastic

behavior (force in stretching depends on elongation and the

rate of the stretch). Research has only begun to document, in

vivo, the short and long-term viscoelastic responses of

human muscles to stretching (Gajdosik, Guiliani, &

Bohannon, 1990; Goeken & Holt, 1993, Magnusson, 1998;

Magnusson et al., 1996a,1996b,1998; McHugh et al. 1992).

Consequently, little is currently known about the clinical

importance of dynamic flexibility. Studies show that

dynamic flexibility accounts for about 44 to 66% of the

variance of static flexibility (Magnusson et al., 1997;

McHugh et al., 1998). However, there is insufficient research

to determine whether static and dynamic flexibility are two

distinct properties or two aspects of the same flexibility

component. More research on the relationship between static

and dynamic flexibility is needed, especially longitudinal

studies of changes in flexibility.

Although dynamic flexibility measurements may provide a

more objective measurement of flexibility, there are

problems with these flexibility variables. The passive

measurements mentioned can only estimate the true

mechanical stiffness of the individual muscles (Latash &

Zatsiorsky 1993). Some studies measure the stiffness of

activated muscle groups (Wilson, Wood, & Elliott, 1991a).

Additionally, differences in scientific and lay terminology

can result in misinterpretations. For example, the use of the

term “elasticity” can be confusing. In biomechanics a greater
3

Normal Static Flexibility

Normal static flexibility occurs somewhere between two

pathologic extremes, anklyosis and hypermobility [Table 1]

(Russek, 1999). Studies using animal models have shown

that normal skeletal muscle extensibility is a function of the

number of sarcomeres in series as well as the amount and

organization of intramuscular connective tissue (Williams &

Goldspink,1978), so muscles can increase or decrease their

length to accommodate the range of motion commonly used.

The early research demonstrated that static flexibility is not a

whole-body characteristic, but like fitness, is specific to areas

of the body (Cureton, 1941; Harris, 1969; Hoshizaki & Bell,

1984). An individual may be quite flexible in one joint

motion but inflexible in another joint. Furthermore, the same

joint can be flexible in one anatomical motion but inflexible

in another motion. Additionally, early work identified a trend

for women to have greater static flexibility than men (Harris,

1969), although much of this effect may be related to

anthropometric differences (Corbin, 1984).

Several different bodies have established normal ranges for

static flexibility tests of the major joints (AAOS, 1965;

ACSM, 1995; AMA, 1988; Gerhardt & Russe 1975). It is not

known, however, if there is an optimal or desirable level for

static flexibility. It is important to appreciate that some

movements involve a greater range of motion than others and

therefore require greater static flexibility. There have been

many reviews on flexibility and stretching (Alter, 1996;

Anderson & Burke, 1991; Clarke, 1975; Corbin 1984;

Corbin & Noble, 1980; Harris, 1969; Holland, 1968; Hutton,

1993; Knapick et al., 1992; Knudson 1998, 1999; Liebesman

& Cafarelli, 1994; Magnusson, 1998; Spaega et al., 1981;

Wilkinson, 1992).

More recently, data have clearly demonstrated that static

flexibility changes across the lifespan. Prior to primary

school, children are quite flexible because of limited

calcification and development of the joints. Static flexibility

varies with physical activity, but overall tends to remain the

same or gradually decrease to about age 12 and then

increases to peak between 15 and 18 years of age (Clarke,

1975). Research has shown significant decreases in static

flexibility and increases in muscle stiffness with aging in

adulthood (Brown & Miller, 1998; Gajdosik, 1997; Gajdosik

et al., 1999; Vandervoot et al., 1992). However, the decrease

in static flexibility with aging is small relative to the typical

variation in flexibility between individuals and the potential

for improvement in flexibility with stretching (Roach &

Miles, 1991). Decreases in flexibility are primarily due to

changes in activity and arthritic conditions (Adrian, 1981)

rather than a specific effect of aging. Therefore, stretching

programs can be effective for individuals of all ages.

Health Benefits of Flexibility

The primary theoretical reason for the inclusion of static

flexibility tests in health-related fitness test batteries is that

flexibility has been associated with injury risk. While it is

logical that limited static flexibility will more likely result in

an overstretched muscle during vigorous activity, there is

little evidence that greater than normal levels of static

flexibility will decrease injury risk (Corbin & Noble, 1980).

If anything, people at both extremes of static flexibility may

be at a higher risk for musculoskeletal injuries (Jones &

Knapik, 1999; Knapik, Jones, Bauman, & Harris, 1992).

There is even less known about the association between

dynamic flexibility and injury risk. Wilson, Wood and Elliott

(1991a) hypothesized that a less stiff musculature would be

less susceptible to muscle strain injury. There is very little

research in this area, but there is preliminary experimental

evidence that a stiffer muscle is more susceptible to

eccentric-induced muscle damage (McHugh et al., 1999). 

With regard to specific injuries, it seems logical that less

flexible back muscles would be related to the incidence of

low-back pain, however, the direct evidence for this link is

not strong. Plowman (1992) reviewed the literature and

found that there was limited support (mixed results) for an

association between lumbar/hamstring flexibility and

occurrence of low-back pain. In support of Plowman’s

conclusions, a large prospective study has recently been

unable to demonstrate a relationship between static

flexibility and subsequent low-back pain in adults (Jackson

et al., 1998). Therefore, it appears that field tests of static

flexibility may not be useful in predicting future low-back

injury.

Although there is little scientific evidence of an association

between flexibility and muscular injuries (Gleim & McHugh,

1997; Jones & Knapik, 1999; Knapik, Jones, Bauman, &

Harris, 1992), there is conflicting evidence on the effect of

stretching on injury. Recent prospective studies have shown

no effect of stretching on injury rate (Pope et al., 1998,

2000), while other studies have reported an effect for

stretching (Cross & Worrel, 1999; Hartig & Henderson,

1999). The studies with larger samples and better controls

(Pope et al., 1998, 2000), support the conclusion that

flexibility and stretching may be unrelated to injury risk.

Currently there is insufficient data to support the common

prescription of stretching programs to modify flexibility

based on the hypothesis of reducing the risk of muscle injury.

Stretching is known to relax (inhibit muscle activation) the

muscle (Avela et al., 1999; Vujnovich & Dawson, 1994) and

has been advocated for the treatment of various muscle

problems (Clarke, 1975; Corbin & Noble, 1980). Static

stretching is clearly indicated and commonly used for the

acute relief of muscle cramps. Similarly, stretching is

commonly practiced to relieve symptoms of delayed-onset

muscle soreness (DOMS). However, recent studies have

shown that stretching before (Johansson et al., 1999; 

Wessel & Wan, 1994) or after activity (Buroker & 

Schwane 1989; Wessel & Wan, 1994) has little or no 

effect on DOMS. Although light stretching is a valuable

activity to maintain static flexibility, there is little
4

evidence that it will decrease symptoms of muscular overuse

like DOMS.

While proper stretching remains a safe physical activity, like

all forms of training there are potential risks to health and

performance. Ballistic or bounding stretches create large

muscle forces that may cause injury (Sapega et al., 1981) and

certain stretching exercises are contraindicated because of

dangerous ligament and tissue loading (Liemohn, Haydu, &

Phillips, 1999; Lindsey & Corbin, 1989; Lubell, 1989). Less

is known about the joint stability-mobility paradox, whereby

increases in range of motion may come at the cost of joint

instability (Corbin & Noble, 1980; Liebesman & Cafarelli,

1994).

In summary, the consensus of the literature is that only

normal levels of static flexibility are needed for a low risk of

injury in most vigorous physical activities. Very high or low

levels of static flexibility may represent an increased risk of

injury. Tests of static flexibility in health-related fitness test

batteries are likely effective instruments for identifying

people at the extremes of the static flexibility distribution.

There is, however, little scientific evidence on which to base

precise flexibility prescriptions for these individuals. In

individuals with normal static flexibility there is little

evidence that stretching or increasing static flexibility will

lower injury rates. There is also a lack of studies on how

differences in dynamic flexibility affect the risk of injury.

Performance Benefits of Flexibility

Since many sports require vigorous joint rotations and often

use extreme positions in the range of motion, there is a

common belief that static flexibility is related to

performance. While there is considerable anthropomteric

research showing static flexibility differences between

athletes from different sports, the retrospective nature of

most studies limits our understanding of these differences

(Clarke, 1975). The scientific evidence for the performance

benefits of flexibility is not as strong as commonly believed

and the claims of benefits from stretching are often

exaggerated (Corbin & Noble, 1980; Gleim & McHugh,

1997). Depending on the nature of the movement, less static

flexibility may actually benefit performance. For example,

less static flexibility has been associated with better running

economy (Gleim et al.1990; Craib & Mitchell, 1996).

Since dynamic flexibility tests measure the increase in

resistance during muscle elongation, it has been

hypothesized to be more related to performance than static

flexibility (deVries, 1986). Several studies have found that

less stiff muscles are more effective in utilizing elastic

energy in stretch-shortening cycle movements (Kubo et al.,

1999, 2000; Walshe, Wilson, & Murphy, 1996; Wilson,

Elliott, & Wood, 1992; Wilson, Wood, & Elliott, 1991b).

Stiffer muscles may have advantages in isometric and

concentric movements (Wilson, Murphy, & Pryor, 1994).

Unfortunately, these studies have used stiffness

measurements of activated muscle groups, so it is unknown if

measures of passive muscular stiffness have similar

relationships to performance. With advances in muscle

imaging, much is being learned about the elastic properties

of human muscle in vivo (Fukunaga et al., 1997; Kawakami

et al., 1998; Ito et al., 1998; Kubo et al., 1999). These kinds

of studies may advance our understanding of the effects of

dynamic flexibility on performance. In the future we may

know if stretching truly decreases muscle stiffness and

consequently improves the muscles capacity to perform in

stretch-shortening cycle actions. Whatever the eventual

relationships, it is likely that the effects of static or dynamic

flexibility on performance are very activity specific (Gleim

& McHugh, 1997).

Despite the universal practice of pre-activity stretching

exercises as part of a warm-up routine, there is little evidence

of a positive short-term effect of stretching on performance.

In fact, recent research has shown that static stretching

creates a short-term decrease (up to 20%) in several kinds of

muscular performance (Avela, Kyrolainen, & Komi, 1999;

Kokkonen, Nelson, & Cornwell, 1998; Rosenbaum &

Hennig, 1995). There is preliminary evidence of a decrease

in strength that can last up to 60 minutes (Fowles & Sale,

1997). The possibility that stretching prior to physical

activities may create a short-term decrease in performance

warrants further investigation.

Recommendations for Flexibility

Development

Testing

Any recommendations for stretching to improve flexibility

should be based on a valid assessment of flexibility using

sound testing procedures. Currently, testing of dynamic

flexibility is still limited to the research setting, because of

problems related to expensive equipment, insufficient

standardization, and data to establish norms. Static flexibility

tests are based on linear and angular measurements of the

motion of a joint or group of joints, and have been classified

as compound (multiple joints) or single joint tests (Corbin &

Noble, 1980). Single joint static flexibility tests are common

clinical measures in the medical professions (AAOS, 1965;

AMA, 1988; Gajdosik & Bohannon, 1987; Norkin & White,

1995; Gerhardt & Russe 1975) and usually involve angular

measurements (goniometers or inclinometers), rather than

linear measurements common in field tests of flexibility .

Single joint tests are considered better measurements of

static flexibility than compound tests because they better

isolate specific muscles and are less affected by

anthropometric variation (Cornbleet & Woolsey, 1996;

Leighton, 1942). For example, the straight leg raise (Goeken

& Holf, 1993) and active knee extension (Gajdosik & Lusin,

1983) tests are the criterion hamstring static flexibility tests

used to validate field tests of hamstring flexibility like the toe

touch or sit-and-reach tests. Professionals must remember,
5

however, that the scores on these tests are subjective and

highly dependent on the subject’s tolerance of the high

tensions (discomfort) during testing.

Most fitness professionals are familiar with several

compound static flexibility tests. The most common healthrelated tests are the sit-and-reach, shoulder lift, and trunk lift.

There has been considerable research on the sit-and-reach

test resulting in quite a number of test variations (Golding,

1997; Holt, Pelham, & Burke, 1999). Fortunately, research

on the sit-and-reach test has shown it to be an moderately

valid measure of hamstring flexibility that is only slightly

affected by anthropometric variations (Hui et al., 1999;

Martin et al.,1998). Hamstring flexibility accounts for most

of the variance in the sit-and-reach test. However, a recent

study showed that 6% of children falsely passed, and 12%

falsely failed the sit-and-reach test relative to the straight leg

raise test (Cornbleet & Woolsey, 1996). People failing the sitand-reach test should be retested with the straight leg test to

ensure they have limited hamstring static flexibility. Current

health-related norms for sit-and-reach tests serve to identify

individuals at the extremes who may be at higher risk of

muscle injuries. However, the sit-and-reach test is not

correlated with low-back flexibility (Martin et al.,1998). A

field test like the modified Schoeber test that uses tape

measurements of spine length (Norkin & White, 1995) may

be more useful in evaluating lumbar flexibility. 

Stretching

The following recommendations for stretching procedures

are based on recent reviews of the viscoelasctic response of

muscle to stretching (Knudson, 1998, 1999). These

recommendations (Table 2) are designed for group exercise

prescription for normal subjects. Remember that flexibility

testing and subject-specific information may require small

variations in flexibility training. For best results, static

stretching or proprioceptive neuromuscular facilitation (PNF)

stretching should be performed at least three times per week,

preferably daily and preferably after moderate or vigorous

physical activity. Four to five stretches for each major muscle

group should be performed, usually during the cool-down

phase of a workout, with each stretch held for 15 to 30

seconds. The cool down is recommended because warmedup tissues are less likely to be injured and the placement of

stretching within the workout does not affect gains in static

flexibility (Cornelius, Hagemann, & Jackson, 1988). The

intensity (force) of each stretch should be minimized, slowly

elongating and holding the stretched position just before the

point of discomfort. Static stretching will create a short-term

increase in range of motion and a decrease in passive tension

in the muscle at a particular joint angle due to stress

relaxation. The effect of stretching on muscle stiffness is not

clear (Knudson, 1999).

It is important for professionals to remember that passive

stretching does create large tensile loads in the muscle, so it

is possible to injure and weaken muscle with vigorous

stretching. Stretching is like other training stimuli that result

in temporary weakening before the body accommodates to

that activity. Assisted stretching procedures like PNF should

be performed with care by trained subjects or sports

medicine personnel. The practice of having athletes passively

stretch partners is not recommended unless the athletes have

been carefully trained in correct procedures and understand

the risk of incorrect stretching.

The efficacy of stretching during the warm-up phase for most

physical activities is controversial. A recent review of the

literature (Knudson, 1999) noted that stretching as part of a

warm-up may have a detrimental effect on performance. It

was suggested that only activities requiring high levels of

static flexibility for aesthetic or scoring purposes (e.g. dance,

gymnastics, diving) should include some static stretching

following a general warm-up. More research is clearly

needed on the role of stretching prior to performance.

Table 2

Stretching Recommendations for 

Group Exercise Prescription

Fitness Variable Recommendation

Frequency At least 3 times per week,

preferable daily and after

moderate or vigorous physical

activity

Intensity Slowly elongate muscle and hold

with low levels of force

Time Up to 4 to 5 stretches held from

15 to 30 seconds. Stretch normally

during the cool-down phase. Be

sure to stretch only muscles that

have been thoroughly warmed-up

from physical activity. Warning:

Stretching in the warm-up prior to

physical activity may weaken

muscles and decrease

performance. 

Type Static or PNF stretches for all

major muscle groups

*Adapted from Knudson (1998, 1999)
6

The President’s Council on 

Physical Fitness and Sports Research Digest 

is now available on-line at http://www.indiana.edu/~preschal

Lee Haney, Chairman

Elizabeth Arendt, M.D., St. Paul, MN

Jeff Blatnick, Halfmoon, NY

Ralph Boston, Knoxville, TN

Don Casey, East Rutherford, NJ

Timothy Finchem, Ponte Vedra Beach, FL

Rockne Freitas, Ed.D., Honolulu, HI

Zina Garrison, Houston, TX

Jimmie Heuga, Avon, CO

Jim Kelly, Buffalo, NY

Judith Pinero Kieffer, Los Angeles, CA

Deborah Slaner Larkin, Pelham, NY

Nikki McCray, Washington, D.C.

Albert Mead III, Atlanta, GA

Jack Mills, Columbia, SC

Ellen Hart Peña, Denver, CO

Ken Preminger, Atherton, CA

Amber Travsky, Laramie, WY

Executive Director—Sandra Perlmutter

Two (2) vacancies

The President’s Council on Physical Fitness and Sports

The President’s Council on Physical Fitness and Sports (PCPFS) was established in 1956 through an Executive Order by

President Dwight D. Eisenhower as part of a national campaign to help shape up America’s younger generation. Today, the

PCPFS serves as an advisory council to the President and Secretary of the Department of Health & Human Services on

matters involving physical activity, fitness and sports to enhance and improve the health of Americans of all ages.

The PCPFS enlists the active support and assistance of individual citizens, civic groups, private enterprise, and voluntary

organizations to promote and improve the physical activity and fitness of all Americans and to inform the public of the

important link which exists between regular activity and good health.

Twenty (20) individuals from the sports, fitness and health fields are appointed by the President to serve as members of the

Council. They are:

Please note that the appropriate language for the citation of this resource is:

The President’s Council on Physical Fitness and Sports Research Digest.

200 Independence Avenue, S.W., Washington, DC 20201 • (202) 690-9000 • FAX (202) 690-5211

Summary

Flexibility is a property of the musculoskeletal system that

determines the range of motion achievable without injury to

a joint or group of joints (Holt, Holt, & Pelham, 1996). Static

flexibility tests measure the limits of the achievable motion

but these limits are subjective. Dynamic flexibility tests are

more objective and measure the stiffness of a passively

stretched muscle group; however, there are no recommended

field tests available at this time. Normal ranges of static

flexibility are well documented for most joints. Major

deviations (top or bottom 20% of the distribution) from the

norm may be associated with a higher incidence of muscular

injury. While there is a theoretical association between

flexibility and several musculoskeletal problems, there are

few prospective studies showing significant associations.

Currently, there is little scientific evidence on which to base

individual prescriptions for static flexibility development

beyond the maintenance of normal levels. More longitudinal

studies of dynamic flexibility may provide a greater insight

into the role of flexibility in health and performance.
7

Physical Activity and 

Fitness Quote

“One important component of 

health-related physical activity 

is a static stretching program performed

following moderate or vigorous 

physical activity. Such a program should

be designed for maintenance of normal

levels of flexibility.”

Duane V. Knudson, Ph.D.

Department of Physical Education and Exercise Science

California State University, Chico

Peter Magnusson, Ph.D.

Team Denmark Test Center, Sports Medicine Research Unit

Bispebjerg Hospital, Copenhagen, Denmark

Malachy McHugh, Ph.D.

Nicholas Institute of Sports Medicine and Athletic Trauma

Lenox Hill Hospital, New York, NY

Please Post

President’s Council on Physical Fitness & Sports

200 Independence Avenue, S.W., Washington, DC 20201

(202) 690-9000 • FAX (202) 690-5211
REFERENCES

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