For additional ancillary materials related to this chapter, please visit thePoint.
Assessments for flexibility and functional movement ability have historically been treated as less significant than muscular and cardiovascular assessments in determining the overall fitness level of an individual. This finding is evident in both the low number of flexibility assessments reported in previous texts and the lack of development of newer assessments. Likewise, the widespread use of functional movement assessments by sport coaches and personal trainers, and inclusion of these assessments in the determination of fitness, prompted their inclusion in this text. Given that an individual’s ability to move through a range of motion (ROM) will determine if that person can properly complete other fitness-related assessments (muscular strength, muscular endurance test, or cardiovascular assessment), it is appropriate to properly assess both flexibility and functional movement as equal in importance to muscular and cardiovascular ability. Flexibility assessment is important because there is an associated decrease in performance of activities of daily living (ADL) with inadequate flexibility. Consequently, maintaining flexibility of all joints facilitates movement and may prevent injury; in contrast, when an activity moves the structures of a joint beyond its full ROM, tissue damage can occur.
This chapter covers commonly used assessments, their strengths and limitations, and available normative data.
 |
Labeling an individual as “flexible” is a misnomer because flexibility is joint specific just as muscular strength and endurance is specific to the muscles involved. Flexibility is not a general term but rather depends on the muscle and joint that is being evaluated, the distensibility of the joint capsule, presence of an adequate warm-up, muscle viscosity, and the tightness of surrounding ligaments and tendons. Therefore, no single test can characterize overall flexibility, but measurements taken at several joints will give an overall impression of flexibility or lack thereof.
The sit-and-reach test is the most widely utilized test for assessment of flexibility mainly because of its simplicity and ability to be performed by just about anyone. The sit-and-reach test is performed either with a sit-and-reach box, a properly placed tape measure, or in a modified manner in a chair and is valid and reliable for evaluating flexibility of the hamstrings, hip, and lower back, which is important to the prevention of chronic lower back pain and the promotion of a healthy lifestyle (9,11).
The sit-and-reach test has been commonly used to assess low back and hamstring flexibility; however, its relationship to predict the incidence of low back pain is limited (4). The sit-and-reach test is suggested to be a better measure of hamstring flexibility than low back flexibility (7). The relative importance of hamstring flexibility to ADL and sports performance supports the inclusion of the sit-and-reach test for health-related fitness testing until a criterion measure evaluation of low back flexibility is available.
The most important limitation of the sit-and-reach test is that it only measures flexibility at a single joint and movement (hip flexion), and although it is an important measure, it cannot be used to generalize overall flexibility of the individual because no other joints are measured. Many fitness batteries use only the sit-and-reach test to measure flexibility, thereby providing an incomplete assessment of overall flexibility. Furthermore, it is not uncommon to see the results of the fitness assessment interpreted as overall flexibility, although only a single flexibility assessment was utilized. This inaccurate interpretation of the results cannot provide an indication of overall flexibility.
The procedure for performing the Canadian trunk forward flexion test, which is measured in centimeters, is provided in Box 7.1. Fitness categories by age groups and gender for the Canadian trunk forward flexion test are provided in Table 7.1. The protocol for the Young Men’s Christian Association (YMCA) sit-and-reach test and fitness data are published elsewhere (6).
Canadian Trunk Forward Flexion (Sit-and-Reach) Test Procedures | |
Pretest: Participants should perform a short warm-up prior to this test and include some stretches. It is also recommended that the participant refrain from fast, jerky movements, which may increase the possibility of an injury. The participant’s shoes should be removed. | |
1. The participant sits with the soles of their feet flat against a sit-and-reach box with the zero mark at the 26 cm. Inner edges of the soles should be 6 in (15.2 cm) apart. (Note the zero point at the foot/box interface and use the appropriate norms.) | |
2. The participant should slowly reach forward with both hands as far as possible, holding this position approximately 2 seconds. Be sure that the participant keeps the hands parallel and does not lead with one hand, or bounce. Fingertips can be overlapped and should be in contact with the measuring portion of the sit-and-reach box. | |
3. The score is the most distant point (cm) reached with the fingertips. The better of two trials should be recorded. To assist with the best attempt, the participant should exhale and drop their head between the arms when reaching. Testers should ensure that the knees of the participant stay extended; however, the participant’s knees should not be pressed down. The participant should breathe normally during the test and should not hold their breath at any time. | |
Norms for the Canadian test are presented in Table 7.1. Note that these norms use a sit-and-reach box in which the “zero” point is at the 26 cm mark. If a box is used in which the zero point is set at 23 cm (e.g., FitnessGram), subtract 3 cm from each value in this table. | |
Reprinted with permission from Canadian Society for Exercise Physiology. Canadian Society for Exercise Physiology — Physical Activity Training for Health (CSEP-PATH) Resource Manual. Ottawa (Canada): Canadian Society for Exercise Physiology; 2013.
Table 7.1 | Fitness Categories for Canadian Trunk Forward Flexion Test Using a Sit-and-Reach Box (cm) by Age and Sex |
Category | Age (yr) | |||||||||
20–29 | 30–39 | 40–49 | 50–59 | 60–69 | ||||||
Sex | M | W | M | W | M | W | M | W | M | W |
Excellent | ≥40 | ≥41 | ≥38 | ≥41 | ≥35 | ≥38 | ≥35 | ≥39 | ≥33 | ≥35 |
Very good | 34–39 | 37–40 | 33–37 | 36–40 | 29–34 | 34–37 | 28–34 | 33–38 | 25–32 | 31–34 |
Good | 30–33 | 33–36 | 28–32 | 32–35 | 24–28 | 30–33 | 24–27 | 30–32 | 20–24 | 27–30 |
Fair | 25–29 | 28–32 | 23–27 | 27–31 | 18–23 | 25–29 | 16–23 | 25–29 | 15–19 | 23–26 |
Poor | ≤24 | ≤27 | ≤22 | ≤26 | ≤17 | ≤24 | ≤15 | ≤24 | ≤14 | ≤22 |
M, men; W, women.
These norms are based on a sit-and-reach box in which the “zero” point is set at 26 cm. When using a box in which the zero point is set at 23 cm, subtract 3 cm from each value in this table.
Reprinted with permission from the Canadian Society for Exercise Physiology. Canadian Society for Exercise Physiology — Physical Activity Training for Health (CSEP-PATH) Resource Manual. Ottawa (Canada): Canadian Society for Exercise Physiology; 2013.
Every joint in the body has an acceptable and normal ROM, which is dependent on various factors, including genetics, orthopedic health, muscular tension, and strength. Laboratory tests usually quantify flexibility in terms of ROM expressed in degrees as measured with either a goniometer or an inclinometer (Fig. 7.1). Measurement of ROM is particularly useful in athletic training, rehabilitation, and conditioning settings; however, the measurements can be misleading if performed without standard procedures, calibration, and instruments. A precise measurement of joint ROM can be assessed at most anatomic joints following the procedures outlined in Box 7.2 and compared with norms provided in Table 7.2.
FIGURE 7.1. Devices used for measuring joint range of motion. A. Standard goniometer (left). B. Mechanical inclinometer (right). (From Swain DP. ACSM’s Resource Manual for Guidelines for Exercise Testing and Prescription. 7th ed. Philadelphia [PA]: Wolters Kluwer; 2014. Fig. 22.5.)
Procedures for Measuring Range of Motion with a Goniometer | |
1. Place the patient in the recommended testing position. | |
2. Stabilize the proximal joint component. | |
3. Move the distal joint component through the available ROM. Make sure the ROM is performed slowly and that the end of the range is attained and end-feel determined. | |
4. Return distal joint component to the starting position. | |
5. Palpate bony anatomic landmarks. | |
6. Align the goniometer, placing the stabilization and movement arms so that they are centered along each body segment according to the landmarks for each joint measurement. | |
7. Read and record the starting position. | |
8. Stabilize proximal joint segment. | |
9. Move the distal component through the full ROM. | |
10. Read and record ROM. | |
Table 7.2 | Range of Motion of Select Single Joint Movements in Degrees |
| Degrees |
| Degrees |
Shoulder Girdle Movement | |||
Flexion | 90–120 | Extension | 20–60 |
Abduction | 80–100 |
|
|
Horizontal abduction | 30–45 | Horizontal adduction | 90–135 |
Medial rotation | 70–90 | Lateral rotation | 70–90 |
Elbow Movement | |||
Flexion | 135–160 |
|
|
Supination | 75–90 | Pronation | 75–90 |
Trunk Movement | |||
Flexion | 120–150 | Extension | 20–45 |
Lateral flexion | 10–35 | Rotation | 20–40 |
Hip Movement | |||
Flexion | 90–135 | Extension | 10–30 |
Abduction | 30–50 | Adduction | 10–30 |
Medial rotation | 30–45 | Lateral rotation | 45–60 |
Knee Movement | |||
Flexion | 130–140 | Extension | 5–10 |
Ankle Movement | |||
Dorsiflexion | 15–20 | Plantar flexion | 30–50 |
Inversion | 10–30 | Eversion | 10–20 |
Adapted from Norkin CC, Levangie PK. Joint Structure and Function: A Comprehensive Analysis. 5th ed. Philadelphia (PA): F.A. Davis; 2011. 588 p.
As with strength testing, consistency and accuracy during flexibility assessment are critical for obtaining meaningful data. Several factors that may compromise accuracy if not performed consistently include anatomic landmark identification, positioning and stabilization of the body, application and stabilization of the measurement device, consistency in technique and protocol, appropriate recording of measures, and recognition of limiting factors or situations during recording. In order for a specific joint ROM to be compared with available norms, standardized landmarks for each measurement should be identified and used whenever possible.
Several commonly measured joints have standard landmarks identified and should be used consistently when measuring ROM. Inaccurate identification of bony or surface landmarks is a common source of error during assessment; therefore, knowledge of surface anatomy is required before accurate measurements can be recorded. In addition to stabilizing body segments, the measurement device must also be properly positioned to ensure data accuracy. The technician should be familiar with the device being used as well as the methodology and biomechanics. Inappropriate placement and use of the device represents a major source of error in many studies examining ROM (4).
The most common instrument used for measuring joint ROM is the two-arm goniometer (see Fig. 7.1). This device is portable, relatively easy to use, and inexpensive. Moreover, the measurements obtained are highly reproducible. The transparent plastic device includes two arms with a protractor for measuring degrees of joint displacement. One arm remains fixed to the proximal articulating segment (e.g., upper arm), and the other adjusts through the ROM with the distal segment (e.g., forearm), measuring the resulting degree of movement. The center of the protractor remains fixed at the joint’s axis of rotation.
Limitations of the conventional goniometer include difficulty stabilizing moving segments and visually determining a vertical axis; however, higher validity and reliability are demonstrated when proper procedures are followed (4). When using a goniometer, the proximal segment of the joint should be stabilized, and the distal segment remains freely moveable. Body position should be conducive to the movement being measured and comfortable for the subject. Joints can be measured in varied positions; however, reliability depends on reproducibility of the position. The patient should be able to maintain the reference position without performing extraneous movement during the measurement.
A newer alternative to the traditional goniometer is a goniometer “app” available for most smartphones (available at the App Store). These apps act as a digital gravity inclinometer by using the accelerometer chip built into most smartphones to calculate the angle of rotation and measure ROM. Several goniometer apps such as Goniometer, MyKnee, and Goniometer Pro (G-Pro) are available for most smartphones. Each has different applications, uses, and price, but all measure angles to within 0.1°. Of particular interest are those apps such as Goniometer for English that allow you to measure angles achieved during movement using video clips you have taken of the individual.
Spinal and other complex movements, including supination, pronation, ankle inversion, and eversion, are difficult if not impossible to assess with a traditional goniometer. Such data are more accurately measured using an inclinometer (see Fig. 7.1). Inclinometers use a universal center of gravity to establish a starting point that remains constant from test to test. The pendulum-weighted inclinometer indicates degrees of motion using a weighted needle and protractor. As with the goniometer, careful placement of the inclinometer is crucial to obtaining an accurate measurement. The American Medical Association (1) suggests that ROM should be measured using the average of three consecutive trials.
