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Copyright © 2019 Section on Women’s Health, American Physical Therapy Association. Unauthorized reproduction of this article is prohibited.
Journal of Women’s Health Physical Therapy © 2019 Section on Women’s Health, American Physical Therapy Association 119
Research Report
ABSTRACT
Background: Biomechanical changes in gait during preg-
nancy have been well studied in walking but not in
running.
Objective: To specifi cally examine adaptations in running
biomechanics pre- to post-pregnancy, especially in the
pelvis and trunk.
Study Design: Pilot study.
Methods: Five regular runners who were pregnant for
the fi rst time participated in this study. Participants ran
at a self-selected speed on an instrumented treadmill
while trunk, pelvis, and lower extremity kinematics were
recorded. Baseline biomechanics were recorded prior to
conception or within the fi rst 14 weeks of gestation. Follow-
up testing occurred at 6 weeks postpartum. Digital surveys
were administered at baseline and 6 weeks postpartum,
as well as at 14, 22, and 30 weeks of gestation. Surveys
queried information regarding training characteristics,
experience of pain, and perceived injury risk compared
with pre-pregnancy.
Results: Pelvis and trunk rotation excursions, sagittal hip
range of motion, and cadence decreased from baseline
to post-pregnancy, whereas stance time, step width, and
sagittal knee range of motion increased. Average running
volume and pace decreased postpartum, although varia-
INTRODUCTION
Exercise during pregnancy has many health benefi ts
for both mother and infant,
1–3 and few exercise-
related complications occur.
4 , 5 The risk of gestational
diabetes reduces with exercise,
2 , 3 and gestational age
at birth can increase.
6 Furthermore, aerobic exercise
improves cardiovascular function during pregnancy.
1
As a result, running during pregnancy is growing in
popularity,
7 in part, because it is a low-cost, high-
accessible form of aerobic exercise.
8–10
Despite the health benefi ts, recreational running
during pregnancy can be diffi cult to maintain, with
more than a quarter of women unable to continue
their regular running practice while pregnant.
11 By
the third trimester of pregnancy, more than 50% of
regular runners report inability to run,
11 with similar
patterns occurring in competitive long-distance run-
ners.
7 Running volume decreases over the course
of pregnancy in both recreational and competitive
long-distance runners,
7 , 11 and running pace has been
shown to slow pre- to post-pregnancy in recreational
1 Michigan Performance Research Laboratory, School of
Kinesiology, University of Michigan, Ann Arbor.
2 Obstetrics and Gynecology, School of Medicine, University
of Michigan, Ann Arbor.
The authors declare no confl icts of interest . This study was
sponsored by adidas AG.
Supplemental digital content is available for this article.
Direct URL citation appears in the printed text and is pro-
vided in the HTML and PDF versions of this article on the
journal’s Web site (http://journals.lww.com/jwhpt/pages/
default.aspx).
DOI: 10.1097/JWH.0000000000000129
Research Report
Restriction in Pelvis and Trunk Motion
in Postpartum Runners Compared With
Pre-pregnancy
Seraphina G. Provenzano 1
Jocelyn F. Hafer , PhD 1
Jillian Peacock , BS 1
Samantha Kempner , MD 2
Jessica Deneweth Zendler , PhD 1
Cristine E. Agresta , PT, PhD 1
Volume • Number • July/September 2019
tion occurred among participants. Abdominal pain was
reported by 2 participants during pregnancy, with 2 partici-
pants reporting increased perceived injury risk.
Conclusion: Taken together, these fi ndings suggest post-
partum runners restrict pelvis and trunk motion and
increase gait stability, potentially as a protective response.
Despite sample size, this pilot study presents initial evi-
dence of biomechanical changes to running gait that occur
pre- to post-pregnancy, which may have implications in
developing support for pregnant and postpartum women
interested in continuing or returning to running.
Key Words: biomechanics , exercise , gait , kinematics ,
pregnancy
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120 © 2019 Section on Women’s Health, American Physical Therapy Association Volume 43 • Number 3 • July/September 2019
Research Report
runners.
11 Altered mechanics may contribute to
changes in running habits during pregnancy and
postpartum.
Several changes may infl uence running mechanics
during pregnancy. These changes include anterior
shift of center of mass,
12 , 13 increased body weight
(BW),
12 altered foot morphology,
14–16 increased
joint laxity,
13 , 17 increased fatigue,
18 increased mus-
culoskeletal pain,
19–22 and increased perceived risk of
injury.
11 To date, only gait mechanics during walk-
ing have been described during pregnancy through
postpartum. Walking speed decreases,
23–26 stance
width increases throughout pregnancy,
27–29 and
stride length decreases.
29 , 30 Correspondingly, double
support time increases between the second and third
trimesters,
30 and ground contact time increases over
the course of pregnancy.
31 These changes in spa-
tiotemporal characteristics of walking gait during
pregnancy have been suggested to be adaptations
to changing body morphology,
28 , 32 and, potentially,
they provide increased stability or reduced likelihood
of falling.
24 , 27 , 28 , 30 In addition to spatiotemporal
changes, kinematics are altered during walking.
Pregnant women display reduced pelvic rotation
25
and frontal plane motion
29 compared with controls.
By the third trimester, pregnant women have been
shown to have greater trunk extension at heel strike,
smaller sagittal plane thorax range of motion, and
greater lateral motion of the spine than matched,
nonpregnant controls.
28 Average anterior pelvic tilt
during stance appears to increase throughout preg-
nancy,
26 , 28 , 32 potentially to adapt to the anterior shift
in center of mass, as this change reverses postpartum
in some individuals.
26
There is a lack of comparable investigation of
running gait during pregnancy and postpartum.
This represents a critical gap in current literature
and prevents appropriate development of running-
specifi c exercise guidelines for runners wishing to
continue to run for aerobic exercise during and after
pregnancy. Therefore, the purpose of this study was
to examine changes in running biomechanics pre- to
post-pregnancy. Focus was placed primarily on trunk
and pelvis motion and spatiotemporal characteristics,
since changes in these parameters have been found in
walking. We hypothesized that transverse and sagit-
tal plane trunk and pelvis motion would decrease
pre- to post-pregnancy in accordance with walking
studies. Because of the small number of participants
who completed the study, we treated our results as an
exploratory analysis of pilot data.
METHODS
All study procedures were approved by the institu-
tional review board at the University of Michigan.
Prior to any study procedures being performed, all
participants provided written informed consent.
Participants
Participants in the study were recruited through
paper fl yers posted in community areas, e-mail com-
munications to running groups and specialty stores,
and identifi cation by a physician of obstetrics and
gynecology (S.K.). Selection criteria for study enroll-
ment were as follows: female, attempting to become
pregnant or at most 14 weeks of gestation, singleton
pregnancy, 18 to 40 years of age, running at least
10 miles per week on average before becoming preg-
nant, and clearance for running during pregnancy
from a health care professional. Participants with
previous pregnancies lasting beyond 14 weeks of ges-
tation or a history of running-related injury or lower
extremity surgery in the last 3 months were excluded.
Ten runners enrolled in the study and completed
baseline testing, and 5 completed the study. The 5
participants who did not complete the study were ini-
tially trying to conceive and did not become pregnant.
Of the 5 participants who did complete the study, 4
were under 14 weeks of gestation at enrollment, and
1 was trying to conceive. They were 33 ± 4 years old
(range: 28-39), 1.65 ± 0.04 m (range: 1.61-1.70) in
height, and 62.14 ± 2.04 kg (range: 58.97-64.10) in
weight. Three participants gave birth via cesarean sec-
tion, and 2 had vaginal deliveries.
Data Collection
Upon enrollment, participants completed base-
line evaluation of running biomechanics in the
laboratory. Follow-up running biomechanics were
collected at 6 weeks postpartum. This time point
was selected according to the American College of
Obstetrics and Gynecology’s general guidelines for
return to exercise.
5 Biomechanical testing consisted
of a 3-minute running trial preceded by 3 minutes
of a walking warm-up and treadmill familiariza-
tion. Participants ran at a self-selected pace they felt
was “easy” and could repeat postpartum. Treadmill
speed was matched between baseline and follow-up
testing.
Surveys were administered electronically (Qualtrics,
Seattle, Washington) at enrollment and 6 weeks
postpartum, as well as at 14, 22, and 30 weeks of
gestation. An extensive literature review on physi-
cal activity and pregnancy informed the develop-
ment of survey questions.
14 , 18 , 22 , 33–35 Questions of
interest (Supplemental Digital Content, available at:
http://links.lww.com/JWHPT/A22 ) inquired whether
participants were currently running, current weekly
mileage, and comfortable training pace. Presence
and location of musculoskeletal discomfort with run-
ning and perception of risk of injury from running
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Journal of Women’s Health Physical Therapy © 2019 Section on Women’s Health, American Physical Therapy Association 121
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compared with those before pregnancy were also
queried. Participants were also asked whether they
used any abdominal or shoe supports.
For biomechanical data collection, participants ran
on a pressure-instrumented treadmill (Quasar, h/p/
cosmos, Nussdorf-Traunstein, Germany) while seg-
ment kinematics were recorded with a 3-dimension-
al (3D) inertial measurement system (MyoMotion;
Noraxon USA, Phoenix, Arizona). Treadmill and
inertial measurement system data were recorded syn-
chronously at 200 Hz during the running trial and
processed with manufacturer software (MyoResearch
3.8/3.10; Noraxon USA, Phoenix, Arizona) to obtain
vertical ground reaction forces (VGRFs) and 3D lower
body and trunk kinematics, respectively . Miniature
9-axis inertial measurement units were placed on
the top of the shoes over the laces, on the lateral
shanks and thighs approximately halfway between
the distal and proximal joint centers, on the center
of the sacrum, and over the T12 spinous process
( Figure 1 ). Sensors were secured to the thorax, legs,
and shoes with fl exible adhesive tape to minimize
motion artifact. The sacral sensor was attached to a
belt worn around the hips. Before collecting running
data, the participant stood in a neutral position with
feet hip-width apart in an area away from magnetic
disturbances to calibrate the sensors, according to
the manufacturer’s directions. Sensor magnetometers
were active for calibration and then turned off for
data collection during the running trial using the
“treadmill mode” of the Noraxon system. This mode
accommodates local magnetic fi eld disturbances from
the treadmill belt motor that could cause erroneous
signals by correcting resulting drift of foot, shank,
and thigh rotations in the horizontal plane to match
the direction of forward running. Because of these
corrections, we did not utilize transverse plane rota-
tions of the lower extremities for subsequent analysis.
Data Analysis
Time-angle and time-force data for the full
3-minute running trials were exported to MATLAB
(MathWorks, Natick, Massachusetts) for subsequent
analysis. Foot strike and toe-off were identifi ed as the
time points when the VGRF surpassed and returned
to 0 N. The time between foot strike and toe-off
was used to calculate stance time, time between left
and right foot strikes was used to calculate cadence,
and the distance between the most medial point of
detected pressure from the left and right feet was used
to calculate step width. Trunk and pelvis transverse
rotation excursion, peak trunk forward pitch during
stance, and right sagittal hip, knee, and ankle excur-
sion throughout the gait cycle (max fl exion − max
extension) were calculated from inertial measurement
unit output. Vertical stiffness was calculated using
running speed, contact time, fl ight time, peak force,
and participant height as inputs to a sinusoidal model
of center-of-mass motion.
36 Vertical stiffness referred
to the compliancy of the lower extremity during run-
ning when center-of-mass motion is modeled via the
spring-mass model.
37
As this was a pilot study, data were reported in
a descriptive fashion. The means for each outcome
variable across each entire trial were compared
pre- to post-pregnancy on a subject-by-subject basis.
For descriptive purposes, group means were also
compared using one-tailed paired t tests, and effect
sizes were calculated (SPSS v24; IBM Corporation,
Figure 1. Setup for inertial measurement units. Units were
placed on the shoes, shanks, thighs, sacrum, and T12 spinous
process as shown before being secured with tape.
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122 © 2019 Section on Women’s Health, American Physical Therapy Association Volume 43 • Number 3 • July/September 2019
Research Report
Armonk, New York). Survey results were considered
both with group means and on a subject-by-subject
basis.
RESULTS
Only one participant reported running consistently
through every survey time point from enrollment
to 6 weeks postpartum. Three of 5 participants
reported running at 6 weeks postpartum, but their
average weekly running volume changed from 33.8
± 19.3 km per week at baseline to 19.3 ± 4.8 km
per week post-pregnancy ( Table 1 ). For these 3 run-
ners, average training pace slowed from 5:35 ± 0:32
min/km at enrollment to 6:00 ± 0:05 min/km post-
partum, although 2 of 3 participants did not change
pace. Reported locations of pain during pregnancy
included the foot, knee, and lower abdomen. Lower
abdomen pain was reported at 22 weeks of gesta-
tion by one participant and at 30 weeks by another.
Women cited discomfort (hip, pelvis, and abdomen)
as the primary reason for stopping running during
pregnancy or postpartum, although feeling discour-
aged and slow and needing a jogging stroller were
also reported reasons. Increased perceived risk of
injury was reported by a participant at 30 weeks
of gestation and by another at 14 and 22 weeks of
gestation and 6 weeks postpartum. One participant
reported decreased perceived risk at 22 weeks. No
participants reported using shoe supports at any time
point, 1 participant reported using an abdominal
stabilizer at 22 weeks of gestation, and 1 participant
reported using an abdominal stabilizer at 30 weeks of
gestation and 6 weeks postpartum.
Mean rotation excursion decreased pre- to post-
pregnancy in all 5 participants at the pelvis ( Figure 2
and Table 2 ) and trunk ( Figure 3 and Table 2 ) by an
average of 23% and 20%, respectively (group mean
decreases of − 3.3 ° ± 2.1 ° at the pelvis and − 5.4 ° ±
5.4 ° at the trunk). Peak trunk pitch increased in 3
participants ( + 5.6 ° ± 2.8 ° ; Figure 4 and Table 2 ) and
decreased in the remaining 2 ( − 2.1 ° ± 2.3 ° ; Figure 4
and Table 2 ). Group mean peak trunk pitch decreased
( − 2.5 ° ± 4.8 ° ). Cadence decreased in 4 partici-
pants ( − 3.4 ± 3.1 steps/min; Table 3 ), and group
mean cadence decreased ( − 2.7 ± 3.1 steps/min) pre-
pregnancy to postpartum. Stance time increased in 4
participants by an average of 6% ( + 0.02 ± 0.004
seconds; Table 3 ), while step width increased by an
average of 44% ( + 0.02 ± 0.01 m; Table 3 ). Vertical
stiffness decreased in 4 of 5 participants ( − 409.0
± 315.2 N/m; Table 4 ), but there were negligible
changes in group mean vertical stiffness ( − 255.2
± 439.0 N/m) and peak VGRF ( − 0.1 ± 0.1 BW).
Sagittal plane range of motion decreased in 4 partici-
pants at the hip ( − 3.3 ° ± 3.1 ° ; Table 5 ) and increased
at the knee ( + 1.6 ° ± 2.1 ° ; Table 5 ). Group mean
sagittal plane hip range of motion decreased ( − 2.6 °
± 3.1 ° ), whereas sagittal plane knee range of motion
increased ( + 1.3 ° ± 2.0 ° ; Table 5 ).
DISCUSSION
A better understanding of typical changes in running
gait mechanics resulting from pregnancy may improve
guidance and recommendations for women wish-
ing to continue running during pregnancy or return
to running postpartum.
38 Since not much is known
about how pregnancy infl uences running gait, the pur-
pose of this pilot study was to determine how running
biomechanics change pre- to post-pregnancy, particu-
larly pelvis and trunk motion. In agreement with our
hypothesis and previous studies of postpartum walk-
ing gait, decreases in transverse rotation excursion at
the pelvis and trunk were found. In addition, running
cadence decreased and stance time and step width
increased postpartum compared with baseline.
Walking studies of pregnant women have shown
increased stance width,
27–29 time of double sup-
port,
30 and foot-ground contact.
31 These changes,
along with decreased walking velocity,
23–26 have been
suggested to improve stability of walking gait by
Table 1. Weekly Running Volume and Pace, Baseline and
6 Weeks Postpartum
Subject
Weekly Running Volume, km Pace per Kilometer, min:s
Baseline Postpartum Baseline Postpartum
1
a 25.7 19.3 5:54 5:54
2 19.3 14.5 5:00 6:03
3 56.3 24.1 5:54 5:54
4
a 19.3 N/A 7:27 N/A
5
a 48.3 N/A 5:35 N/A
a Reported musculoskeletal pain or increased perceived injury risk.
Figure 2. Mean pelvis rotation excursion at baseline and
6 weeks postpartum by subject. All runners decreased
transverse plane pelvic rotation postpartum compared with
baseline.
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Journal of Women’s Health Physical Therapy © 2019 Section on Women’s Health, American Physical Therapy Association 123
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maximizing base of support and reducing mediolater-
al motion.
24 , 27 , 28 , 30 Changes found in this study could
be explained similarly. Our study design did not allow
women to reduce running speeds for post-pregnancy
biomechanics testing. As a result, runners may have
promoted gait stability by lowering cadence, increas-
ing stance time, and widening step width. These
changes could reduce the likelihood of falls due to
instability.
24 , 27 , 28 , 30
Changes in pelvis and trunk rotation were consis-
tent across runners. These fi ndings are comparable
with those of pregnant walking studies showing
limited midline rotation
25 , 28 and sagittal trunk range
of motion
28 during pregnancy. One reason for a
decrease in transverse rotation with running dur-
ing and post-pregnancy could be pain avoidance.
Decreased pelvis rotation was suggested to reduce
lower back and hip pain in a case study of a post-
partum runner.
39 Pregnant women often report low
back pain,
11 , 28 leading to speculation that pregnant
women alter trunk and pelvis motion to reduce low
back pain.
28 In contrast, the 5 runners in the current
study had few reports of pain and did not report low
back pain during running at any survey time point.
This suggests that there may be motivations beyond
pain to reduce pelvis and trunk rotation postpartum.
For instance, structural changes in the pelvis and
trunk may have resulted in reduced motion postpar-
tum. Increased ligamentous laxity about the pelvis
is typical with pregnancy and postpartum
22 and
may require increased activity of surrounding mus-
culature. Increased muscle activity not only would
improve force closure of the pelvic ring
40 but could
also result in reduced pelvic excursion, particularly
rotation. Likewise, reduced trunk motion may be
caused by restrictions in trunk mobility through-
out pregnancy due to increased abdominal girth
and weight. Determining whether pelvis and trunk
motion returns to pre-pregnancy patterns once the
structural factors associated with pregnancy and
childbirth have resolved, or at least plateaued, is of
critical importance. Our results suggest that pelvis
and trunk motion does not resolve to pre-pregnancy
patterns by the time physicians often clear women to
return to running. Studies extending further into the
postpartum period are needed to determine whether
Table 2. Trunk and Pelvis Kinematics, Baseline and 6 Weeks Postpartum
Subject
Peak Forward Trunk Pitch During Stance, ° Pelvis Transverse Rotation Excursion, ° Trunk Transverse Rotation Excursion, °
Baseline Postpartum Baseline Postpartum Baseline Postpartum
1
a − 2.4 − 1.9 15.8 12.1 30.1 28.5
2 5.6 9.3 21.2 15.5 23.1 23.0
3 10.5 4.1 13.3 12.9 25.6 16.0
4
a 23.8 16.1 7.7 5.5 29.2 16.7
5
a 8.0 5.5 14.0 9.4 22.6 19.2
P .15 .01 .04
Effect size 0.26 0.77 0.56
a Reported musculoskeletal pain or increased perceived injury risk.
Figure 3. Mean trunk rotation excursion at baseline and
6 weeks postpartum by subject. All runners decreased
transverse plane trunk rotation postpartum compared with
baseline.
Figure 4. Mean peak forward trunk pitch at baseline and
6 weeks postpartum by subject. Three runners increased
and 2 decreased trunk pitch postpartum compared with
baseline.
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124 © 2019 Section on Women’s Health, American Physical Therapy Association Volume 43 • Number 3 • July/September 2019
Research Report
or when these movement patterns resolve to pre-
pregnancy ranges. Changes in lower extremity sagit-
tal motion (hip and knee) may be due to increased
muscle activation and restricted motion about the
pelvis, and it is possible that runners attempted
to compensate for this decreased hip motion with
increased sagittal knee range of motion.
Although pain may not independently infl uence
mechanics locally (ie, at the location of pain), it does
appear to be important to running habits. Two run-
ners did report lower abdominal pain at different
time points during pregnancy. Both women who
reported lower abdominal pain at a survey time point
also reported stopping running by the next, sug-
gesting that pain in this region may be particularly
infl uential in terms of changes in running behavior.
Reports of lower abdominal pain also occurred later
in pregnancy, at 22 and 30 weeks of gestation, which
is consistent with descriptions of when pregnant
women typically stop running.
7 , 41
Table 3. Spatiotemporal Gait Characteristics, Baseline and 6 Weeks Postpartum
Subject
Cadence, steps/min Stance Time, s Step Width, m
Baseline Postpartum Baseline Postpartum Baseline Postpartum
1
a 168 166 0.30 0.31 0.05 0.07
2 166 166 0.29 0.31 0.04 0.06
3 172 171 0.27 0.28 0.09 0.08
4
a 163 160 0.37 0.36 0.04 0.07
5
a 171 163 0.30 0.32 0.11 0.12
P .06 .04 .05
Effect size 0.50 0.46 0.52
a Reported musculoskeletal pain or increased perceived injury risk.
Table 4. Peak VGRF and Vertical Stiffness, Baseline and 6 Weeks Postpartum
Subject
VGRF, BW Vertical Stiffness, N/m
Baseline Postpartum Baseline Postpartum
1
a 1.94 1.80 4209 4090
2 1.89 1.78 4374 3827
3 2.03 2.03 5545 4748
4
a 1.62 1.61 2564 2924
5
a 1.76 1.70 4098 3916
P .38 .13
Effect size 0.03 0.30
Abbreviations: BW, body weight; VGRF, vertical ground reaction force.
a Reported musculoskeletal pain or increased perceived injury risk.
Table 5. Lower-Limb Joint Sagittal Excursions, Baseline and 6 Weeks Postpartum
Subject
Hip Flexion Excursion, ° Knee Flexion Excursion, ° Ankle Flexion Excursion, °
Baseline Postpartum Baseline Postpartum Baseline Postpartum
1
a 37.1 34.2 29.5 29.5 49.4 48.0
2 36.1 36.3 25.1 25.7 48.9 46.2
3 35.3 32.5 23.0 27.8 40.4 45.3
4
a 37.0 29.5 27.6 28.2 24.7 43.4
5
a 44.1 44.0 27.8 28.3 47.1 39.4
P .06 .10 .32
Effect size 0.48 0.36 0.06
a Reported musculoskeletal pain or increased perceived injury risk.
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ACKNOWLEDGMENTS
This study was sponsored by adidas AG.
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Increased perception of injury risk was also report-
ed in survey responses at 22 and 30 weeks of gestation
and, contrary to reports of pain, appeared to contrib-
ute more directly to changes in running mechanics.
Changes in running mechanics pre-pregnancy to post-
partum appear to favor increasing stability. Improving
gait stability could refl ect a response to reports of
increased perceived injury risk by reducing the likeli-
hood of falls. If avoidance of abdominal pain were
a main reason for women changing their running
mechanics pre- to post-pregnancy, we would expect
modifi cations in joint loading or variables related to
minimizing impact on the body during running. In
this study, some runners decreased their vertical stiff-
ness post-pregnancy, which could reduce impact load-
ing by allowing less energy absorption at the lower
extremity.
41 Counterintuitively, however, they main-
tained the same peak VGRF while reducing cadence,
2 factors that would not promote reduced force trans-
mission to the body and risk of subsequent pain.
41
Several limitations exist for this pilot study. The
greatest limitation was the small sample size. In addi-
tion, only 2 time points for data collection were used.
Biomechanical testing during pregnancy may provide
additional insights into why running habits and per-
ceived risk of injury change throughout gestation. We
did not obtain muscle activity patterns during testing
or collect passive range-of-motion measurements. This
limits our interpretation of the underlying mechanism
driving biomechanical changes. Examination of lower
back and abdominal muscle activation, as well as pas-
sive range of motion, could reveal the cause of these
changes and provide targets for intervention. Finally,
we did not test postural control or document balance
confi dence or fear of falling perception. Testing pos-
tural and gait stability in later pregnancy and postpar-
tum could reveal whether the spatiotemporal changes
observed were adopted to increase stability during
pregnancy. Future studies would benefi t from a larger
sample size, data collections throughout pregnancy,
and addition of physical examination measurements.
CONCLUSIONS
This pilot study presents initial evidence of biome-
chanical changes to running gait that occur pre- to
post-pregnancy. Our fi ndings suggest that, compared
with pre- or early pregnancy, postpartum runners
restrict trunk and pelvis rotation and alter spatiotem-
poral characteristics in a way that could compensate
for increased laxity and increase gait stability. These
preliminary results may provide targets for future
studies to more closely examine the mechanisms
behind these changes and the development of return-
to-run exercises or guidelines for the postpartum
population.
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126 © 2019 Section on Women’s Health, American Physical Therapy Association Volume 43 • Number 3 • July/September 2019
Research Report
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