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Lengthening the Hamstring Muscles
Without Stretching Using “Awareness
Through Movement”
Background and Purpose.
Passive stretching is widely used to increase muscle
flexibility, but it has been shown that this process does not produce long-term
changes in the viscoelastic properties of muscle as originally thought. The
authors tested a method of lengthening hamstring muscles called “Awareness
Through Movement” (ATM) that does not use passive stretching.
Subjects.
Thirty-three subjects who were randomly assigned to ATM and control groups
met the screening criteria and completed the intervention phase of the study.
Methods.
The ATM group went through a process of learning complex active
movements designed to increase length in the hamstring muscles. Hamstring
muscle length was measured before and after intervention using the Active
Knee Extension Test.
Results.
The ATM group gained significantly more
hamstring muscle length (
7.04°) compared with the control group
1.15°).
Discussion and Conclusions.
The results suggest that muscle length
can be increased through a process of active movement that does not involve
stretching. Further research is needed to investigate this finding. [Stephens J,
Davidson J, DeRosa J, et al. Lengthening the hamstring muscles without
stretching using “Awareness Through Movement.”
Phys Ther
. 2006;86:1641–
1650.]
Key Words:
Awareness Through Movement, Feldenkrais method, Hamstring, Muscle lengthening, Stretching.
James Stephens, Joshua Davidson, Joseph DeRosa, Michael Kriz, Nicole Saltzman
Physical Therapy . Volume 86 . Number 12 . December 2006
1641
(
tors to the control of human movement and are
involved in a wide range of activities from
running and jumping to forward bending dur-
ing sitting or standing and a range of postural control
actions. Hamstring muscle strains are the most common
muscle injuries in athletes.
1
The proposed etiology
includes insufficient flexibility, strength (force-
generating capacity) impairment or imbalance, and dys-
synergic contraction that can place excessive strain on
the hamstring muscles.
2
Static stretching of the ham-
string muscles, to maintain flexibility and improve per-
formance,
2– 4
has been proposed as a proactive and
preventive strategy and is now in common use. Studies
with collegiate football players
5
and military basic train-
ees
2,6
document the success of this strategy in reducing
the rates of lower-extremity injuries.
A variety of methods have been used to increase ham-
string muscle flexibility, including static stretch,
14
pro-
prioceptive neuromuscular facilitation,
15
dynamic range
of motion,
16
and active motion in the neural slump
position.
17
None of these methods, however, uses a
process of active motion without pushing or holding at
end-range to achieve its intended results.
“Awareness Through Movement” (ATM) is a process of
verbally guiding a person through an activity during
which movements usually are performed slowly and
gently. It is thought that this process facilitates the
learning of strategies for improving organization and
coordination of body movement by developing spatial
and kinesthetic awareness of body-segment relationships
at rest and during motion, awareness of ease of move-
ment, reducing effort in action, and learning the feeling
of longer muscles in action.
18,19
This process has been
shown to improve balance and coordination in people
with multiple sclerosis
20
and balance and mobility in
people with chronic cardiovascular accident.
21
Reduced hamstring muscle flexibility has been impli-
cated in lumbar spine dysfunction, with a number of
studies
7–10
showing a strong positive correlation between
decreased hamstring flexibility and low back pain. Other
researchers
10 –13
have suggested that hamstring muscle
function in a variety of movements is part of a coordi-
nated motor program and thus the appropriate periods
of lengthening and shortening and perhaps even the
degree of lengthening itself may be a learned part of the
motor control process.
There has been limited study of this approach to ham-
string muscle lengthening. Researchers in Australia
found no effect of ATM on hamstring muscle length
with a very brief intervention.
22,23
The purpose of our
study was to test the hypothesis that ATM can be used
effectively to increase the active length of the hamstring
J Stephens, PT, PhD, CFP, is Assistant Professor, Physical Therapy Department, College of Health Professions, Temple University, 3307 N Broad
St, Philadelphia, PA 19140 (USA). Dr Stephens is a Certified Feldenkrais Practitioner (CFP) and member of the Feldenkrais Guild of North
America (FGNA). He has served as Chair of the Research Committee of FGNA. There are no financial ties. Address all correspondence to Dr
Stephens at: jstephen@temple.edu.
J Davidson, PT, DPT, CSCS, is Sports Physical Therapist, Golf Performance Specialist, and Certified Strength and Conditioning Specialist, The
Sports Medicine and Performance Center at The Children’s Hospital of Philadelphia, King of Prussia, Pa.
J DeRosa, PT, MSPT, is Owner/Physical Therapist, Eastern Shore Physical Therapy, Linwood, NJ.
M Kriz, PT, MSPT, is Staff Physical Therapist, Bonita Springs Sports and Physical Therapy, Bonita Springs, Fla.
N Saltzman, PT, MSPT, is Physical Therapist, Physical Therapy Consultant Group, Scottsdale, Ariz.
Dr Stephens provided concept/idea/research design and institutional liaisons. Dr Davidson provided data collection. Dr Stephens, Dr Davidson,
and Mr Kriz provided writing, data analysis, project management, facilities/equipment, clerical support, and consultation (including review of
manuscript for submission). Assistance with writing, data analysis, and clerical support also was provided by Mr DeRosa and Nicole Saltzman. The
authors acknowledge the assistance of Melinda Bartscherer, who facilitated institutional relations in her role as Acting Chair of the Institute for
Physical Therapy Education at Widener University when the study was done and Jeff Lidicker, PhD, at the College of Health Professions, Temple
University, for his assistance with statistical analysis.
This study was approved by the Widener University Committee for the Protection of Human Subjects.
This research, in part, was presented as a poster at PT 2000: Annual Conference and Scientific Exposition of the American Physical Therapy
Association; June 5–8, 2000; Cincinnati, Ohio.
This article was received July 1, 2004, and was accepted August 11, 2006
.
DOI: 10.2522/ptj.20040208
1642 . Stephens et al
Physical Therapy . Volume 86 . Number 12 . December 2006
T
he hamstring muscles are important contribu-
muscles. We chose to look at active length because we
believe that this measure is more meaningful than
passive length in relation to normal functional move-
ment and motor control.
ATM group was made up of 7 male and 11 female
subjects who ranged in age from 22 to 36 years
(25.9
7.89 degrees. The con-
trol group was made up of 6 male and 9 female subjects
who ranged in age from 21 to 27 years (23.9
Method and Materials
1.9) and
had a pretest hamstring muscle length measurement of
140.66
Subjects
Fifty-one subjects were recruited using posters and word
of mouth from the population of graduate students and
faculty at the Widener University, Chester, Pa, campus.
The purpose of the study was explained, and volunteers
signed an informed consent form approved by the
Widener University Committee for the Protection of
Human Subjects.
8.19 degrees. There were no statistically signifi-
cant differences between ATM and control groups based
on age, sex, or pretest hamstring muscle length.
Instrumentation
Active knee extension hamstring muscle length was
measured as the highest value in the range of knee
extension using a PEAK Motus motion analysis system.*
Accuracy of angle measurement for this system has been
reported to be less than 0.1 degree, with an intraclass
correlation coefficient (ICC) of .99.
24
An S-VHS Pana-
sonic CL-700 digital video camera was placed 7.6 m
(25 ft) from each subject and centered on a line
perpendicular to the plane of motion of the subject’s
knee. Movement was recorded on a Sanyo editing S-VHS
recorder at 60 frames per second and digitized using
PEAK Motus software. An alignment apparatus similar to
that described by Scholz and Millford
24
was constructed
of 3.81-cm (1.5-in) diameter PVC pipes. Two vertical
uprights 0.91 m (3 ft) in length were connected by a
crossbar. The footings of each upright were secured to a
standard plinth by 2 Stanley Quick Grips.
†
Reliability of
knee angle measurements was determined using ICCs
(2,3). A set of 3 repeated measurements from each
subject was used for pretest and posttest calculations.
The pretest ICC was .976, and the posttest ICC was .995.
Subjects qualified for the study if they did not have a
history of orthopedic problems, including surgery or
injury to the back, pelvis, or lower extremities or neuro-
logic dysfunction (eg, multiple sclerosis, cerebral palsy,
or peripheral neuropathy) within 1 year from the begin-
ning of the study. Subjects also were excluded from the
study if they had an active knee extension angle greater
than 165 degrees (full extension
Seven of the 51 subjects did not meet the screening
criteria because their hamstring muscle length exceeded
the maximum standard. Six subjects withdrew for per-
sonal reasons before group assignment. The remaining
38 subjects were randomly assigned to a group that
received ATM intervention (ATM group [n
Experimental Procedures
20]) or a
group that received no intervention (control group
[n
Measurement protocol.
The hamstring muscle length of
all subjects who met the screening requirements was
measured using the Active Knee Extension Test
(AKET)
25
1 week prior to beginning the intervention.
Hamstring muscle length was measured again 1 to 2 days
after the end of the intervention period. Subjects were
positioned supine on a standard 0.9-
18]). Five subjects (2 in the ATM group and 3 in the
control group) were dropped from the study after group
assignment. Two of these subjects left the graduate
program, 2 subjects missed the final data collection
because of sickness or travel commitments, and 1 subject
withdrew because of an acute ankle sprain sustained
while running during the period of the study. Thirty-
three subjects (18 in the ATM group and 15 in the
control group) met the screening criteria and com-
pleted the intervention phase of the study.
6-ft)
plinth under the alignment apparatus. A 10.2-cm-wide
(4-in-wide) Velcro strap
‡
was placed around the subject
at the level of the anterior superior iliac spine to stabilize
the pelvis and lumbar spine. An additional 10.2-cm-wide
Velcro strap was placed over the left thigh to stabilize the
pelvis and left lower extremity. The subjects’ right hip
was flexed to 90 degrees until the anterior thigh was just
touching the crossbar of the alignment apparatus.
1.8-m (3-
All subjects were asked to refrain from beginning any
new physical activity, including hamstring muscle
stretching, that had not been part of their regular
activity prior to the 3-week period of the intervention.
Subjects in the ATM group were asked to perform a
15-minute ATM session 5 times per week guided by an
audiotaped ATM lesson sequence. Subjects in the con-
trol group performed their regular daily activities. The
* Peak Performance Technologies Inc, 7388 S Revere Pkwy, Suite 901, Centen-
nial, CO 80112. The Panasonic camera and Sanyo VCR were obtained as part of
the PEAK Motus system.
†
Stanley Tools Group, 480 Myrtle St, New Britain, CT 06053.
‡
Velcro USA Inc, 406 Brown Ave, PO Box 5218, Manchester, NH 03103.
Physical Therapy . Volume 86 . Number 12 . December 2006
Stephens et al . 1643
SD) and had a pretest hamstring muscle
length measurement of 141.96
3.8) (X
180 degrees) mea-
sured using a quick-screen active knee extension test in
which the subject lay supine with the hip flexed to 90
degrees and actively extended the knee.
17
If active knee
extension was judged to fall outside of the desired range
as marked on a plexiglass template, based on visual
assessment, subjects were excluded.
continued for the collection of 6 full repetitions for the
pretest and posttest for each subject. Repetitions 4
through 6 only were used as measures of hamstring
muscle length to allow all subjects the same amount of
practice and warm-up time before the measured trials.
Subject data were identified by number only, and the
researcher responsible for determining knee angle from
the PEAK data was not aware of the group to which each
subject was assigned.
Figure 1.
Setup for measuring hamstring muscle length using PEAK Motus motion
analysis system.
Intervention.
The ATM intervention was given over a
3-week period and consisted of an initial group training
lesson and a home practice program. All subjects in the
ATM group participated in the initial 30-minute class-
room lesson targeting movements of the right lower
extremity. The lesson consisted of an introduction plus 3
movement segments, with each segment covering varia-
tions of movements requiring lengthening of the ham-
string muscle in different postural configurations. This
lesson was recorded on audiotape, and a copy was given
to each subject in the ATM group for independent
home practice during the course of the study. The
Appendix gives a description of the audiotaped ATM
lessons.
Reflecting markers 2.54 cm (1 in) in diameter were
placed on the subjects’ right lower extremity over the
greater trochanter, the middle of the lateral joint line of
the knee, and the lateral malleolus. Proper alignment of
the right thigh parallel to the vertical post of the
alignment apparatus and perpendicular to the horizon-
tal surface of the plinth was verified using the video
monitor (Fig. 1).
Each segment of the lesson began and ended with a body
scan in the supine position. This scan was designed to
make subjects aware of their quality of neuromuscular
control, including the rate and depth of breathing, the
level of neuromuscular system tension throughout the
body from the jaw to the feet, and the effort involved in
simple movements such as rolling the leg left and right.
The first movement segment began with the subjects
lying on their left side. In the second movement seg-
ment, subjects sat in a long-sitting position. The third
movement segment was done in the standing position,
beginning with the hips and knees flexed and the pelvis
posteriorly tilted. In each segment, movements were
suggested in which subjects flexed and extended the
right knee, tilted the pelvis forward and back, and
rotated the right hip with the head and upper extremi-
ties in various positions. The goal was for subjects to
learn to extend the knee, medially (internally) rotate the
extending leg, and anteriorly tilt the pelvis at the same
time, an organization of movements designed to
lengthen the hamstring muscle from both ends.
Subjects were told to maintain the position of the
anterior thigh in light contact with the crossbar of the
alignment apparatus. They were permitted to use a towel
wrapped around the posterior right thigh just proximal
to the knee throughout the test procedure to maintain
anterior thigh contact with the crossbar. The starting
position for the test was with the anterior thigh touching
the crossbar of the alignment apparatus and the right
knee in a relaxed and fully flexed position. One repeti-
tion of a knee extension movement consisted of moving
the knee into extension until a feeling of resistance from
the stiffness of the hamstring muscle stopped the move-
ment and then returning to the starting position. Sub-
jects were told to begin a series of extension movements
when one of the researchers gave a “go” signal and to
continue until a “stop” signal was given. Movements were
paced at one per 2 seconds using a watch and giving
verbal cues of “up” during the extension phase and
“down” during the flexion phase of the movement. The
timer gave a “ready” signal 3 seconds before the begin-
ning of the procedure. The researcher responsible for
data collection began recording with the PEAK system
just before the beginning of the first repetition and
As with all other movements in the lesson, these move-
ments were done slowly and continuously, with the
subjects resting when tired, and within a comfortable
range of movement, noticing when effort in other areas
of the body interfered with these specific movement
intentions and trying to reduce those efforts and breathe
easily through the entire process. Subjects were told
explicitly not to push into the end-range of knee exten-
sion as they might if they were doing active or passive
1644 . Stephens et al
Physical Therapy . Volume 86 . Number 12 . December 2006
end-range stretching. Variations of the options of rotat-
ing the hip medially and laterally (externally), extending
and flexing the knee, and tilting the pelvis were sug-
gested. Subjects in the ATM group were asked to use the
guidance of the audiotaped ATM lesson sequence until
they were comfortable with the process of exploring the
movements suggested, at which time they could proceed
without the guidance of the audiotape. All subjects were
asked to keep an activity log that included leisure and
exercise activities and for the ATM group also included
the frequency and duration of their ATM practice.
Table 1.
Change in Hamstring Muscle Length Measured in Degrees
a
Group
Time
X
SD
ATM (n
18)
Pretest
141.96
7.89
Posttest
149.00
7.40
Control (n
15)
Pretest
140.66
8.19
Posttest
141.81
7.61
a
Full extension
180 degrees. ATM
Awareness Through Movement.
Table 2.
Two-Factor Analysis of Variance With One Repeated Measure (Time)
and Hamstring Muscle Length as the Dependent Variable
Data Analysis
The dependent variable of interest was hamstring mus-
cle length as measured by the maximum active knee
extension angle. Three trials per subject from each
measurement session were recorded, and the mean was
used for data analysis. A 2-factor repeated analysis of
variance (ANOVA) (group
df
F
P
Group
1
2.807
.104
Time
1
17.779
.001
a
Group
time
1
9.177
.005
a
time) was used with time as
the single repeated measure.
26
An alpha level of .05 was
used as the criterion for significance of difference.
a
Significant difference.
Subjects in the ATM group practiced independently
over a period of 3 weeks and differed widely from each
other in their number of practice sessions and total
minutes practiced. Furthermore, because all subjects in
the ATM group did not follow the same practice sched-
ule, their postintervention hamstring muscle length
measurements were done with different periods of delay
following the time of their final practice session. To
assess the possible effects of these practice and delay
variables on the outcome measure of hamstring muscle
length, a
post hoc
multiple regression analysis was done.
26
The number of practice sessions, total minutes of prac-
tice, and delay (in days) were used as independent
variables with the dependent variable of hamstring mus-
cle length change within the ATM group. In this analysis,
a significance level of
9.1°–17.5°). One person representing
each of these levels was interviewed using open-ended
questions to assess their understanding of and experi-
ence and strategies in practicing the ATM lessons. These
qualitative data were used to help interpret the quanti-
tative data collected.
12.9°, range
Results
The mean change in hamstring muscle length in the
ATM group was
1.15 degrees (Tab. 1). There
was a significant increase in hamstring muscle length
over time and an interaction of group
time, indicating
an increase in hamstring muscle length in the ATM
group compared with the control group (
P
.005)
.05 would indicate that the
independent variable made a significant contribution to
the prediction of the outcome measure of hamstring
muscle length change. All statistical analyses were done
using SPSS version 11.0.4 for Macintosh.
§
(Tab. 2, Fig. 2).
Table 3 shows the number of practice sessions, total
minutes of practice, and change in hamstring muscle
length for each subject in the ATM group. There was
wide variation in the amount of practice among subjects.
The range for number of sessions was 7 to 18, and total
minutes of practice ranged from 80 to 300 over the
3-week period of the intervention. The delay between
the last practice session and the final hamstring muscle
length measurement ranged from 1 to 10 days. The
regression analysis (Tab. 4) showed that there was no
significant effect on hamstring muscle length change in
the ATM group as a result of number of practice
sessions, the total number of minutes of practice, or
amount of delay between the last practice session and
the final hamstring muscle length measurement.
At the end of the intervention period, subjects in the
ATM group were asked the question: “From your expe-
rience of ATM, would you say that this process is
different from stretching, as you understand it?” After
the hamstring muscle length change analysis was com-
pleted, subjects in the ATM group were divided into 3
levels based on the amount of muscle length change.
F
iv
e subjects achieved no change in muscle length
(X
4.6°–
6.8°). Seven subjects achieved a large amount of change
6.1°, range
§
SPSS Inc, 233 S Wacker Dr, Chicago, IL 60606.
Physical Therapy . Volume 86 . Number 12 . December 2006
Stephens et al . 1645
(X
7.04 degrees compared with the
control group change of
3.4°–2.6°). Si
x
subjects achieved a
moderate amount of change (X
0.1°, range
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