Cruz (2012) gait and CP

BACKGROUND: Cerebral palsy (CP) is defined as a group of disorders of the development of movement and posture, causing activity limitation that are attributed to non-progressive disturbances occurred in the developing fetal or infant brain (Gage, 2004). CP is known as one of the most common childhood disabilities with an incidence of about 2-3 per 1,000 live births each year (Chang et al., 2010). In most cases of CP, gait and balance play a key role in participating in activities of daily living and other physical activities. The effects of exercise programs on land have been well documented; however, there are very few studies that involved aquatic intervention in the CP population. Aquatic exercise is gradually gaining popularity among the CP rehabilitation field and has been viewed to be beneficial for children with neuromuscular impairments such as CP (Kelly & Darrah, 2005). Water properties can establish an intervention protocol that can help children with CP improve balance and gait function in a supportive environment. The unique quality of buoyancy can reduce joint impact and support postural control (Kelly & Darrah, 2005). Buoyancy enables initiation of independent movement possibilities that are less likely to be achieved on land-based exercise (Fragala-Pinkham et al., 2008). Water resistance can aid children with CP and improve muscular strength (Hutzler et al., 1998). Warm water temperatures have been known to be effective for decreasing muscle tone while exercising in the water (Getz et al. 2007). Few studies have examined the effects of aquatic exercise on gait and balance in children with CP.

OBJECTIVE: To examine the gait outcomes of children with CP after 6-week aquatic exercise program.

SETTING: All data collection and intervention procedures was held at the Center of Achievement, California State University, Northridge (CSUN).

PARTICIPANTS: A total of 4 children was recruited from local schools in the greater Los Angeles ares. Inclusion criteria are: a) diagnosis of spastic diplegic or hemiplegic CP, b) age between 7-17 years old, c) medical clearance for adapted exercise or aquatic exercise, d) ability to walk independently with or without an assistive device, e) Gross Motor Function Classification System (GMFCS) levels I-III, f) ability to follow verbal instructions and communicate in English, g) ability to participate in a exercise program in and out of the water for up to 30-40 minutes. INTERVENTION: The children participated in an aquatic exercise program in a 40-minute session, three times per week for 6 consecutive weeks. The aquatic exercise program consists of warm-up, gait and balance exercises, and cool-down.

MEASURES: The participants were measured on kinemtaic gait parameters (hip flexion and extension, knee flexion and extension, and ankle plantar-flexion and dorsi-flexion) x and spatial-temportal gait variables (% stance and swing phase, velocity, cadence, step width and stride length). RESULTS: There were no trends among participants as a whole. However, individal trends for improvement in kinematic and spatial-temporal variables was observed for each participant.

CONCLUSION: Although there were no systematic changes whithin the group after the 6-week intervention, individal changes in ankle, knee, and hip range of motion presented individual improvements based on each particpant’s deviation in gait pattern in which trends for improvemts display that group aquatic exercise is a useful mode of exercise to maintain and improve gait paramerters in children with CP.

 

CALIFORNIA STATE UNIVERSITY, NORTHRIDGE

The Effects of Aquatic Exercise on Gait Parameters in
Children with Cerebral Palsy
A thesis submitted in partial fulfillment of the requirements
For the degree of Masters of Science
In Kinesiology

By
Robert D. De La Cruz

May, 2012

ii

The thesis of Robert De La Cruz is approved:

____________________________________ _______________
Mai Narasaki Jara, MS Date

____________________________________ _______________
Konstantinos Vrongistinos, Ph.D. Date

____________________________________ _______________
Taeyou Jung, Ph.D., ATC, CAPE, Chair Date

California State University, Northridge

iii

DEDICATION

To my mom & dad,
Who has courageously given me the strength for my education
To my family,
Who have always encouraged nothing but the best results
To my friends,
Who have made this process all that more enjoyable

iv

ACKNOWLEGDEMENTS
I would gratefully like to acknowledge my committee members for their
knowledge and unique expertise. A special thanks to Dr. Jung, my committee chair, for
believing that I could thrive in this field, and providing continuous support. Dr.
Vrongistinos for his knowledge in biomechanics and optimism. Mai Narasaki Jara for
challenging and providing her expertise in aquatic exercise.
This project was made possible by the contributions of colleagues, staff,
community members of the Center of Achievement, and the individuals who participated
in this study. I would like to thank Jennifer OConnor, Leora Gabay, Michelle Borja,
Sabrina Anostasis, Ashley Kokawa, Amber Hubbard, and Michael Lee who gave so
generously of their time and support.
As a student associate I would like to thank all the students whom I have learned
from because they allowed me to teach them. To them I am most grateful. A teacher is
not successful without his students. Thank you for contributing to my continued success.

v

TABLE OF CONTENTS
Signature Page.....ii
Dedication.......iii
Acknowledgements.....iv
Abstract.....viii
INTRODUCTION.......1
DEFINITION & ETIOLOGY1
CLASSIFICATION........2
MOTOR FUNCTION3
TREATMENT3
LITERATURE REVIEW5
CP & GAIT.....5
CP & MUSCLE CONTRACTURE...5
CP & SPASTICITY...7
CP & MUSCLE WEAKNESS...8
CP & MOBILITY...9
CP & EXERCISE...9

vi

CP &AQUATIC EXERCISE...11
METHODS16
Participants...16
Setting...16
Instrumentation.17
Intervention Protocol17
Data Outcome Measrues...18
Data Collection Procedures..18
Human Subjects Review...19
RESULTS..20
Participant 1...22
Participant 2...29
Participant 3...35
Participant 4...42
DISCUSSION48
CONCLUSION..52

vii

REFERENCES..53
APPENDIX A

MEDICAL RELEASE FORM..56

APPENDIX B

CHILD ASSENT TO BE IN A HUMAN RESEARCH PROJECT..57

viii

Abstract
The Effects on Gait Outcomes of Aquatic Exercise in
Children with Cerebral Palsy

By
Robert De La Cruz
Masters of Science in Kinesiology

BACKGROUND: Cerebral palsy (CP) is defined as a group of disorders of the
development of movement and posture, causing activity limitation that are attributed to
non-progressive disturbances occurred in the developing fetal or infant brain (Gage,
2004). CP is known as one of the most common childhood disabilities with an incidence
of about 2-3 per 1,000 live births each year (Chang et al., 2010). In most cases of CP, gait
and balance play a key role in participating in activities of daily living and other physical
activities. The effects of exercise programs on land have been well documented; however,
there are very few studies that involved aquatic intervention in the CP population. Aquatic
exercise is gradually gaining popularity among the CP rehabilitation field and has been
viewed to be beneficial for children with neuromuscular impairments such as CP (Kelly
& Darrah, 2005). Water properties can establish an intervention protocol that can help
children with CP improve balance and gait function in a supportive environment. The
unique quality of buoyancy can reduce joint impact and support postural control (Kelly &

ix

Darrah, 2005). Buoyancy enables initiation of independent movement possibilities that
are less likely to be achieved on land-based exercise (Fragala-Pinkham et al., 2008).
Water resistance can aid children with CP and improve muscular strength (Hutzler et al.,
1998). Warm water temperatures have been known to be effective for decreasing muscle
tone while exercising in the water (Getz et al. 2007). Few studies have examined the
effects of aquatic exercise on gait and balance in children with CP.
OBJECTIVE: To examine the gait outcomes of children with CP after 6-week aquatic
exercise program.
SETTING: All data collection and intervention procedures was held at the Center of
Achievement, California State University, Northridge (CSUN).
PARTICIPANTS: A total of 4 children was recruited from local schools in the greater
Los Angeles ares. Inclusion criteria are: a) diagnosis of spastic diplegic or hemiplegic
CP, b) age between 7-17 years old, c) medical clearance for adapted exercise or aquatic
exercise, d) ability to walk independently with or without an assistive device, e) Gross
Motor Function Classification System (GMFCS) levels I-III, f) ability to follow verbal
instructions and communicate in English, g) ability to participate in a exercise program in
and out of the water for up to 30-40 minutes.
INTERVENTION: The children participated in an aquatic exercise program in a 40-
minute session, three times per week for 6 consecutive weeks. The aquatic exercise
program consists of warm-up, gait and balance exercises, and cool-down.
MEASURES: The participants were measured on kinemtaic gait parameters (hip flexion
and extension, knee flexion and extension, and ankle plantar-flexion and dorsi-flexion)

x

and spatial-temportal gait variables (% stance and swing phase, velocity, cadence, step
width and stride length).
RESULTS: There were no trends among participants as a whole. However, individal
trends for improvement in kinematic and spatial-temporal variables was observed for each
participant.
CONCLUSION: Although there were no systematic changes whithin the group after the
6-week intervention, individal changes in ankle, knee, and hip range of motion presented
individual improvements based on each particpants deviation in gait pattern in which
trends for improvemts display that group aquatic exercise is a useful mode of exercise to
maintain and improve gait paramerters in children with CP.

1

INTRODUCTION:
Cerebral Palsy (CP)
DEFINITION & ETIOLOGY:
Cerebral palsy (CP), widely referred to Littles Disease named after William John
Little in the end of the 19th Century, is defined as a group of disorders of the development
of movement and posture. CP is a disorder that causes activity limitations and is
attributed to non-progressive disturbances that occurred in the developing fetal or infant
brain (Gage, 2004). CP is also known as one of the most common childhood disabilities,
with an incidence of about 2-3 per 1,000 live births each year (Cogher et al., 1992).
Causes of CP are unknown and its risk factors can be identified as complications before
(prenatal) and during (perinatal) birth, up to the first 6 years (postnatal) of life
(Panteliadis&Strassburg, 2004). Among all the risk factors associated with CP, prenatal
risk factors are responsible for the majority of CP cases (Panteliadis&Strassburg, 2004).
Panteliadis and Strassburg (2004) state that prenatal risk factors include complications
that cause damage to the developing brain such as congenital brain malformation,
chromosomal defects, congenital infections, familial predisposition to CP, maternal drug
or alcohol abuse, maternal mental retardation, maternal hyperthyroidism or epilepsy,
incompetent cervix and or third trimester bleeding. According to Hinhcliffe (2003),
motor disorders of cerebral palsy are often accompanied by disturbances of sensation,
cognition, communication, perception, behavior, and or by seizures that ultimately limit
an individual with CP in various motor capabilities.

2

CLASSIFICATION:
CP is divided into four major classifications to describe different movement
impairments: spastic (muscle spasm), ataxic (tremors), athetoid or dyskinetic (mixed
muscle tone), and hypotonic (limp musculature). When a child is diagnosed with CP,
motor function is observed to have one or a combination of these different characteristics.
According to Cogher et al. (1992), spastic cerebral palsy is the most common type,
occurring in 75% of all cases. The affected area of the body can be identified as
hemiplegia (one side), diplegia (lower extremities), monoplegia (one single limb),
triplegia (three limbs) and quadriplegia (all four limbs).
Knowing what motor functions children with CP are able to perform is an
important part to implementing a successful treatment protocol. A test to measure motor
function in children with CP is called the Gross Motor Function Measure (GMFM). The
GMFM is a validated instrument that enables comprehensive quantitative evaluation of
changes in motor function in children with CP (Panteliadis&Strassburg, 2004). The
GMFM tests activities and positions in lying, rolling, sitting, crawling, kneeling,
standing, walking, running, and jumping skills. Each child is classified into different
levels depending on the severity of the childrens mobility called the Gross Motor
Function Classification System (GMFCS). The GMFCS consists of levels I through V
and classifies children with CP and their ability to ambulate. According to Gage (2004),
level I describes the mildest case of CP, where the child is able to ambulate without any
restrictions, and level V, indicates when a child with CP is completely immobile. To
assess and distinguish mobility options, a child with CP is classified using the GMFCS.
Once parents and primary physicians know what functional limitations the child possess,

3

treatment options can be implemented according to functional mobility from their
GMFM scores.
MOTOR FUNCTION:
Locomotion is defined as someone who walks with or without an assistive device
and is able to utilize transportation with a manual or motorized wheelchair (Lepage et al.,
1998). In children with CP, irregular posture, spasticity, and weakness all contribute to
functional limitations associated with gait. Typical walking patterns associated with CP
include jump knee, crouch, true equinus, apparent equinus, recurvatum, and
stiff knee gait (Chambers, 2001). These typical gait patterns are usually accompanied
by fixed flexion contractures and or hyperextension of the hip, knee, and ankle that limit
a child with CP to walk efficiently (O'Byrne et al., 1998 & Chambers, 2001). According
to Wu et al. (2010), spasticity is a common impairment that interferes with motor
function that is characterized by increased tone with a tendency to flexor spasm along
with a flexed posture. Active co-contraction of the leg muscles is generated and spasticity
occurs before the first step during walking takes place.
TREATMENT:
Surgery or less invasive treatments such as the use of orthotics are immediate
solutions to treating gait deviations in CP. However, a surgical solution known as
Selective Dorsal Rhizotomy (SDR) for spasticity, has been known to have complications
due to surgically incising a nerve root not associated with spasticity (Gage, J.R., 2004).
Additionally, orthotics, primarily prescribed by a physician, are not readily available for
the general public and hinder treatment options for children with CP. A treatment option

4

that may help promote participation, activity, and physical fitness in children with CP is
exercise. Exercise is a more resourceful type of treatment option to improving gait with
children with neuromuscular disorders because it can be done without any restrictions
(Gage, J.R., 2004). There have been various intervention studies that incorporate land
based exercise to help with gait deviations in children with CP (Verschuren et al., 2007,
Blundell et al., 2003, Lee et al., 2008, Eeek et al., 2008, Scholtes et al., 2010, & Unger et
al., 2006). The need for other forms of rehabilitation should be explored so that the CP
population can incorporate an exercise intervention that will have a consistent protocol to
improving gait in children with CP.

5

LITERATURE REVIEW:
CP &GAIT:
Typical gait patterns in children with CP include jump knee, crouch, true equinus,
apparent equinus, recurvatum, and stiff knee gait (Chambers, H.G., 2001). These gait
patterns are usually accompanied by involvement at the hip, knee, and ankle. Davids et
al. (2004) and Winters et al. (2010) uses various gait abnormalities in children with CP
through the use of quantitative gait analysis, using 3-dimentional high-speed motion
picture cameras or VICON system. This method of gait analysis has been used to record
various gait parameters during walking interventions. Davids et al. (2004) and Winter et
al. (2010) investigated the gait outcome after strengthening exercise in children with CP.
Both studies have identified various mechanisms to understand pathological gait in
children with CP and monitored progression after gait interventions. Davids et al. (2004)
also utilized this quantitative analysis to identify characteristics of common gait
abnormalities associated with the knee in children with CP. Whereas Winters et al.
(2010) took advantage of this instrument to classify participants into subsequent groups
based on kinematic variables made in three major joints of the lower extremity (ankle,
knee and hip). Although Davids et al. (2004) and Winters et al. (2010) show the use
motion analysis system to classify gait associated in children with CP, research on
interventions that can help improve gait deviations in children with CP were not
addressed in these studies.
CP & MUSCLE CONTRACTURE:
Children with CP experience muscle contractures that cause movements in walking

6

to be stiff and floppy (Gage, J.R., 2004). Contractures have been a major concern in
treating children with CP. Orthopedic treatments has been suggested to treat various
contractures in children with CP. With more severe cases of contractures, Gage (2004)
refers to a sequence of the diving or birthday syndromes in which the child has an
operation every birthday following a yearlong of therapy. Consequently, Gage (2006)
states that following the periods of therapy and each surgical procedure, the child may
end up in excessive morbidity and permanent weakness, becoming less mobile than when
the child was first treated.
Less invasive treatments such as using orthotics and or walking aides have shown
to improve gait in children with CP (Balaban et al., 2007). Studies have shown that using
devices increases participation and maximizes performance in various activities of daily
living in children with CP (Balaban et al., 2007 & Park et al., 2001). Orthotics, such as
Hinged Ankle Foot Orthosis(AFO), has shown to normalize ankle motion during
dorsiflexion range and improve walking speed, stride length, and single support time, and
decrease double support time in children with CP (Balaban et al., 2007). Walking aids,
such a posterior walkers, has been shown to be more suitable for facilitating an upright
posture during walking in children with CP (Park et al., 2001). However, using these
devices may not solve the deviation in gait that children with CP possess, but rather help
with the abnormal deviations in gait children with CP experience. Although these devices
have been shown to improve posture for children with CP, they do not promote
independent walking that may result in a less active child when participating in different
activities and sports.

7

CP &SPASTICITY:
Spasticity hinders children with CP during walking and engaging in physical
activity. Ensegerg et al. (2000) and Chambers et al. (2001) documented mechanisms
associated with spasticity in gait patterns with ambulatory children with CP. Enseberg et
al. (2000) found that spasticity occurs when the ankle is in plantar-flexed position during
the gait cycle. Whereas Chambers et al. (2001) concluded that spasiticity involves
abnormal knee motion that is related to dynamic conditions during muscle shortening or
muscle contraction. Selective Dorsal Rhizotomy (SDR), a surgical procedure that
selectively severs problematic nerve roots in the spinal cord, and injection of botulinum
toxin type A (botox) to the muscle, are procedures used for treating spasticity (Steinbok,
2001 &Davids et al., 2004). However, literature reveals that administering botox or
incising a nerve root might do more damage than good for the use of treatment of
spasticity in CP (Gage, 2004). Botox may have to be administered multiple times to
decrease the effects of spasticity, and for others, it may only be temporary relief from
spasticity. Additionally, incising of a nerve root may have adverse side effects if there
were to be any complications. For example, permanent paralysis of the legs and bladder,
permanent impotence, sensory loss and or numbness in the legs, wound infection and or
leakage of the spinal fluid through the wound are risks that should be taken into account
when deciding to do the procedure (Panteliadis&Strassburg, 2004). Rather than taking
risks to help improve gait, other forms of treatment should be implemented so that
spasticity does not limit mobility and activity in children with CP.

8

CP &MUSCLE WEAKNESS:
Muscle weakness is another limiting factor that limits mobility, participation, and
activity in children with CP. Many studies have incorporated land-based exercise
interventions to improve motor function in children with CP (Verschuren et al., 2007,
Blundell et al., 2003, Lee et al., 2008, Eeeket al., 2008, Scholtes et al., 2010, & Unger et
al., 2006). Interventions on land have emphasized variations in strength training as an
exercise regimen to increase strength and a wide range of functional motor skill activities.
Lee et al. (2008) have shown therapeutic effects of strengthening exercise on gait
function, such as increased muscle strength without significant adverse effects or increase
in muscle tone in children with CP. Lee at al. (2008) emphasized home exercise programs
twice a week and a small group session once a week with a physiotherapist which
consisted of easy to heavy load and sets of ten repetitions for each muscle group.
Whereas, Eek et al. (2008) showed that strengthening programs have a positive effect on
ambulation, such as ability to balance on one leg, negotiating obstacles and climbing
stairs that may promote independence in children with CP. Eek et al. (2008) used a
strengthening program targeting the muscles groups of the lower limbs that consists of
warm up stretching exercises, squat to stand, lateral step up, stair walk up and down,
isotonic exercise of lower limb muscles, isokinetic exercise utilizing a bicycle, and a cool
down exercise for five consecutive weeks. Although the studies had different exercise
protocols, both studies demonstrated positive outcomes in gait with children with CP
such as increased muscle strength and stride length.

9

CP & MOBILITY:
Mobility is described as the ability to move from place to place, participation with
their family and peers, and the ability to function optimally in everyday life (Bludell et
al., 2003). Various strength exercises, such as functional strength training interventions,
have increased mobility during physical activity and help promote a healthier lifestyle in
children with CP (Verschuren et al., 2007 &Bludell et al., 2003). Verschurem et al.
(2007) developed a functional based exercise program that were task specific that
included running and changing direction, step-ups, and negotiating stairs repeatedly, as
well as muscle strengthening exercises in circuit training format. The 12-month follow up
concluded that participation in an exercise program maintains fitness levels and enhances
health related quality of life in children with CP. Blundell et al. (2003) uses a 4-week
circuit-training program task specific to lower limb strength and functional performance
in children with CP. Following the intervention, eight weeks after documented all
improvements in strength function performance and functional motor performance was
maintained. Follow-up tests concluded participation in functional strength related
exercise had positive results in maintaining physical activity.
CP & EXERCISE:
Various studies have also focused on enhancing muscle weakness to improve gait
function such as gait speed in children with CP (Lee et al., 2008, Eek et al., 2008,
Scholtes et al., 2010, & Unger et al., 2006). Eek et al. (2008) investigated the influence of
strength related exercises on gait outcomes in children with CP. The 8-week training
period consists of an exercise protocol of three times a week with a physiotherapist and

10

twice per week at home. The sessions consisted of a low intensity warm up,
individualized programs with strength training exercises, followed by stretching
exercises, which concluded a more efficient gait that increased power during push off and
making the push off phase of gait easier for the ankle plantar-flexors to push off actively
in children with CP (Eek et al. (2008). In addition, this study showed a significant
increases in stride length and plantar-flexor generating power during push off, as well as
improved stability during the stance phase in walking. Lee et al. (2008) developed a 5-
week strengthening program targeting the muscle groups of the lower limbs 3 times per
week and the duration of 60 minutes each session. The program had subjects perform
stretching exercise during warm up, squat to stand, lateral step up, stair stepping, isotonic
exercise of lower limb muscles, isokinetic exercise utilizing a bicycle, and then followed
by a cool down similar to the warm up. The experimental group had a significant increase
in gait speed and stride length, single limb support, and maximal hip flexion during
walking. This study concluded that strength is an important aspect of normal motor
control that is deficient in patients with CP. Although both studies had unique
individualized exercise protocols to improve strength, both studies did not have the same
results in improving gait velocity in children with CP. Lee et al. (2008) had an increase in
gait speed in his study, whereas Eek et al. (2008) had no change in velocity in children
with CP.
Other strength related interventions focus on a more functional task related exercise
to investigate its effects on mobility in children with CP (Blundell et al., 2003, Scholtes et
al., 2010, & Liao et al., 2007). Blundell et al. (2003) established functional exercises such
as step ups, sit to stand, leg presses, and treadmill walking to determine an increase in

11

functional movement pattern in children with CP .Scholets et al. (2010) followed three
functional exercise protocols for the lower extremity with weighted vests that consists of
sit to stand, lateral step up, and half knee rise to improve mobility in children with CP.
Whereas, Liao et al. (2007) emphasized loaded sit to stand exercise and utilized weighted
vests to add resistance for progression. All functional task specific intervention studies
concluded that an increase in isometric strength following training. However, Blundell et
al. had gains in improvement in mobility and ambulation in children with CP due to
functional performance that was maintained over time. Scholtes et al. (2010) concluded
that the exercise protocol projected in this study increased isometric muscle strength of
the knee and hip, but improvements in mobility did not carry over due to lack of
supporting elements related to balance and coordination. Liao et al. (2007) emphasized
functional strengthening exercises in loaded sit to stand exercise alone, but did not
incorporate elements in improving gait function in children with CP. Overall, specific
task related interventions to improve gait should be established when finding a proper
exercise protocol for children with CP.
CP &AQUATIC EXERCISE:
An alternative intervention that addresses the factors that limit mobility and
improve gait in children with CP is aquatic exercise. Aquatic exercise can be used for
children with CP and address posture, spasticity, and muscle weakness. Aquatic exercise
has been viewed to be beneficial for children with neuromuscular impairments such as
CP (Kelly &Darrah, 2005). There are very few aquatic interventions in literature for
children with CP to improve gait function. Due to various properties of water, aquatic
exercise can establish a proper intervention protocol that will improve gait function in

12

children with CP. Kelly &Darrah (2006) report that exercise in the water appeals to
children with CP because of the unique quality of buoyancy of water that reduces joint
loading and impact, and decreases the negative influences of poor balance and postural
control. Buoyancy enables initiation of independent movement possibilities that are less
likely to be achieved on land-based exercise. Water property such as viscous drag may
help with strengthening weakened limbs that child with CP experience. Gage (2004)
states, strengthening exercises may exacerbate spasticity and limit motor function when
doing exercises. Warm temperatures used in aquatic setting have been known to generate
therapeutic properties that decrease muscle tone (Getz et al. 2007). In addition, the
resistive forces of buoyancy and viscous drag permit a variety of aerobic and
strengthening activities that can be easily be modified to help accommodate the limited
range of motor abilities in children with CP.
Interventions in an aquatic setting have increased physical competence and social
acceptance in children with CP (Getz et al. 2007). The use of the Pediatric evaluation of
disability inventory (PEDI) and the Aquatic independence measure (AIM) to evaluate
functional performance in self-care, mobility and social function and to assess the
childrens level of skill acquisition in the aquatic environment was used. Getz et al.
(2007) states that children who participate in the aquatic exercise program may initiate
multiple social interactions, provide greater sensory stimulation and feedback, as well as
commence independence in children with CP. However, this study does not express gait
outcomes or functional related activities that children with CP lack. Self-assurance in
children with CP and physical competence allows a stepping-stone to improving gait in
children with CP. Competence gained in an aquatic setting may transfer over to walking

13

on land and may improve mobility and physical activity in children with CP.
Others studies investigate that aquatic based exercise for children with CP can
improve gait function (Fragala-Pinkham et al., 2008, &Hutzler et al., 1998). Posture,
spasticity, and muscle weakness are three primary reasons why children with CP are less
engaged in physical activity and participation (Fragala-Pinkham et al., 2008). Although
land based exercise have shown to improve gait function in children with CP, the use of
an aquatic setting may be more beneficial for children with CP. Due to waters unique
properties, aquatic exercise can greatly help to improve gait function in children with CP
by eliminating the factors that hinders physical activity in children with CP. Other studies
incorporate aquatic exercise and children with CP that have shown positive effects on
vital capacity, muscle strength, and motor skill (Fragala-Pinkham et al., 2008, &Hutzler
et al., 1998). However, further research is needed to find the effects of aquatic exercise
and investigate gait outcomes to improve gait function in children with CP.
By using an aquatic exercise intervention, gait associated with spatiotemporal and
kinematic variables can be improved in children with CP due to a proper aquatic gait-
training regimen. Properties of water can help to aid in creating a proper exercise
protocol that can address mobility limitations to improve gait variables in children with
CP. With gait improvements due to aquatic exercise, children with CP will be able to
walk more efficiently with greater velocity and increasing stride and step length, as well
as increasing how much children with CP are able to ambulate. Furthermore, children
with CP will have a greater range of motion on their lower extremities as a result of
improved contracture. With the use of aquatic exercise to improve gait, children with CP
are able to walk with a more efficient gait pattern other than typical gait abnormalities

14

they experience.
The aquatic setting is suitable for children with CP to improving gait and can also
be adapted to other disabilities other than CP. Provide scientific evidence to the CP
population that aquatic exercise can improve gait deviation in children with CP and
treating other neuromuscular disorders that can improve gait deviations. Additionally,
present clinicians with evidence based research on aquatic exercise interventions in
children with CP and other neurological disorders so that clinicians are able to
incorporate and encourage the use aquatic exercise program to their rehabilitation
regimen. Overall, exercise and physical activity is beneficial for children with and
without disability to promote overall health. The use of an aquatic environment is an
alternative source to getting children with disabilities physically active to prevent
obesity and other complications associated with inactivity.
There is little research that focuses on the effectiveness of aquatic exercise in
improving gait parameters in children with CP. Recent studies that incorporate aquatic
exercise have measured respiratory function, increased participation, and physical
activity (Getz et al. 2007, Fragala-Pinkham et al., 2008, &Hutzler et al., 1998). Aquatic
therapy has grown popularity in the rehabilitation field to treat many neuromuscular
disorders. (Fragala-Pinkham et al., 2008). The unique properties of water such as
buoyancy and viscous drag help to create an exercise environment suitable for the CP
population. Buoyancy properties allow children with CP to move freely in the water by
decreasing excessive stress on their joints associated with gravity (Fragala-Pinkham et
al., 2008). Viscous drag creates resistance that can be used to implement various
exercise intensities (Fragala-Pinkham et al., 2008). Aquatic exercise can be used to keep

15

children with CP physically active as well as help improve functional limitation due to
their disability (Fragala-Pinkham et al., 2008). The use of an aquatic setting will not
only give children with CP an environment that is different from the usual land based
exercise, but can open a new dimension that children with CP have not experienced
before. This may help children with CP be motivated in participating in an exercise
program as well as be more independent due to buoyancy properties that an aquatic
setting can offer.
Gait abnormalities in children with CP have been a primary concern that hinders
participation and physical activity in the CP population (Gage, J.R., 2004). Due to motor
limitation that is associated with contracture, spasticity, and weakness, children with CP
experience a much slower gait speed as well as cadence to compensate with their
abnormalities in gait. Children with CP have less stride and step length as well as single
support time due to lack of coordination and balance associated with CP. Additionally,
contracture in children with CP hinders movement through a full range of motion in
various joint angles of the lower extremity. Decreased ankle range of motion is the
primary reasons that children with CP are unable to walk efficiently. Toe walking is the
most common type of gait that children with CP experience. By using an aquatic exercise
regimen, its unique properties can establish a proper exercise regimen and improve
spatiotemporal and kinematic variables in children with CP. Therefore, the purpose of
this study is to investigate the effects of a 6-week aquatic exercise program in improving
gait parameters in children with CP.

16

METHODS
Participants
Children will be recruited from local elementary schools in the city of Northridge.
All participants will have to be ambulatory children with mild form of CP, GMFCS level
I-III. All participants should obtain a medical clearance form from their primary care
physicians prior to participation in this group aquatic exercise (Appendix A).
Inclusion criteria are: a) diagnosis of spastic diplegic or hemiplegic CP, b) age between 7-
17 years old, c) medical clearance for adapted exercise or aquatic exercise, d) ability to
walk independently with or without an assistive device, e) Gross Motor Function
Classification System (GMFCS) levels I-III, f) ability to follow verbal instructions and
communicate in English, g) ability to participate in a exercise program in and out of the
water for up to 30-40 minutes.
Exclusion Criteria are: a) nstable seizures, b) medicalsurgical treatment for spasticity 6
months prior to the study (Botox or Selective Dorsal Rhizotomy), and c) current
participation in aquatic therapy.
Setting
The study took place at the Center of Achievement (COA) at California State
University, Northridge. The aquatic intervention was held in the main therapy pool where
the water depth was 1.5 meters and the temperature was maintained at 35 degree Celsius
(95 degree Fahrenheit). Data collection using 3-Dimensional gait analysis took place in
the expansion room of the COA. Multiple data measurements were used to test joint

17

range of motion of the hip, knee, and ankle. In addition to velocity, cadence, stance and
swing phase, and step width and stride length. At a total of 4 multiple data measurements
were taken at week 0 (pre intervention), week 3 (mid intervention), week 6 (post
intervention), and week 7 (follow-up intervention).
Instrumentation
The study used the VICON Bonita System (VICON, Oxford, UK, 2010),using 7 high-
speed infrared cameras that I captured each participants walking. VICON Nexus
computer softwarewas also used to analyze and measure data received from participant's
walking.

Intervention Protocol

Participants exercised in an aquatic group exercise setting following baseline data
collection. The aquatic group exercise was instructed by a researcher on the pool deck
where heshe lead the various exercises. Certified lifeguard ensured childrens safety in
the water as well asresearch assistance whom will behelping the children with each
exercise. A total of 18 sessions occurred, 3 times a week, for a total of 40 minutes.
The aquatic group exercise began with a 10 minute warm-up that consisted of water
adjustment and stretching as the moveable pool floor was adjusted. All children were to
stand or sit in the middle of the pool while lifeguard adjusted the pool floor to ranges of
childrens chest to waist level. Exercises consists of 10 minutes of warm-up (water
adjustment and stretching),10 minutes of gait training (forwardbackward walking, side-

18

steping, toe-walking, and heel-to-toe walking), 10 minutes of balance training (wide-to-
narrow stance, tandem standing, and one-leg standing), and 10 minutes of cool down
(group play and modified fun game). All gait and balance exercises were modified to
mimic various gamessports to help keep childrens attention span on specific exercises
performed.

Data Outcome Measrues

The participants were measured on kinemtaic gait parameters (hip flexion and
extension, knee flexion and extension, and ankle plantar-flexion and dorsi-flexion) and
spatial-temportal gait variables (% stance and swing phase, velocity, cadence, step width
and stride length) .
Data Collection Procedures

During Initial data collection, all participants submitted medical clearance obtained
from their primary physician before their participation in this study. Data collection
procedures were approved by CSUN Institutional Review Board . Each parent and
guardian reviewed and signed the informed concent form while the child reads and signs
the child accent form. During pre, mid, post, and follow-up data collection, all
participants were ask to change into bicycle shorts or tightly fit clothing. Reseacher
attached reflective markers to the lower extremity bony landmarks. Static data were
captured as the participants stand still in the middle of a 10-meter walkway. Gait trials
will then be captured as the participants will be asked to walk a 10-meter walkway 3

19

times at a comfortable walking speed and 3 times at their maximum velocity (30-second
rest periods between trials and 2-minute rest period between comfortable and maximum
walking speed tests).
Human Subjects Review

The Human Subjects protocol was approved by the Standing Advisory Committee for
the Protection of Human Subjects (SACPHS) at California State University, Northridge.

20

RESULTS
The purpose of this study was to investigate the effects of aquatic exercise on gait
parameters in children with Cerebral Palsy (CP). Kinematic (hip, knee, and ankle) and
spatial-temporal (stance and swing phase, cadence, velocity, step width, step length, and
stride length) variables were measured in this study. The outcomes of kinematic and
spatial-temporal measures were analyzed independently using the Polygon software.
Descriptive statistics were used to illustrate the main results of this study. Visual analysis
of bar graphs was used to depict any main changes in trends.
Four participants from local elementary schools in the city of Northridge were
recruited for this study. Two participants with mild spastic hemiplegia CP with Gross
Motor Classification System (GMFCS) levels of I (participants 2 and 3), and two
participants with mild spastic diplegic CP with GMFCS level of II-III (participants 1 and
4) completed the 6-week aquatic intervention; thereafter, 7-week follow-up was then
analyzed. Data analysis was conducted on the affected side of the spastic hemiplegic CP
and the most affected side of the spastic diplegic CP participants. Anthropometric data of
all participants is listed in detail in Table 1.
It was hypothesized that there would be trends for improvement in all kinematic
measurements variables; sagittal hip, knee, and ankle range of motion. It was also
hypothesized that there would be trends for improvement in all spatial-temporal
measurement variables; cadence, velocity, stance and swing phase, step width, step
length, step time, stride length, and stride time. The results of each participant are
described individually.

21

Table 1 Participant anthropometricphysical characteristics information

Participants 1 2 3 4
Age (yrs.) 10 14 7 10
Height (mm.) 1397 1550 1275 1322
Weight (kg.) 60 39.6 28 29
Gender Female Female Female Male
CP Dx.GMFCS DiplegicII HemiI HemiI DiplegicII

22

Participant 1
Participant 1 was a 10 year old girl with mild spastic diplegia, GMFCS level II-
III. According to her physical therapist, left side was mostly affected with walking
characteristics of crouch and left slap foot gait. Participant was also diagnosed with a
secondary physical disability of developmental delay and had a medical history that
consists of a fractured tibia and femur 6 years prior to this study.
There were no systematic changes in hip and knee kinematics observed
throughout gait cycle (Figure 1 & Figure 2). However, sudden ankle plantar-flexion was
observed in participants kinematic baseline (pre intervention) during initial contact of
gait cycle (Figure 3). Mid, and post intervention displays a smooth transition in plantar-
flexion during initial contact and maintains its effect at follow-up intervention.
At baseline, stance phase showed an increasing trend throughout the study and
adversely effects swing phase of the participants gait cycle(Figure 4). Initial stance
phase was at 55% and increases to 57% (4%) during mid-intervention,58% (5% from
baseline) during post-intervention, and 62%(13% from baseline) during follow-up
intervention.
Velocity displays a decreasing trend throughout the study (Figure 5). At baseline,
velocity was at 1.37ms and decreases to .84ms (39%) at mid-intervention, .75ms (45%
from baseline) during post-intervention, and.66ms (52% from baseline) at 7-week
follow-up. Cadence (stepsminute) also had a decrease trend throughout the study (Figure
6). At baseline, cadence was at 189 sm and decreases to 131sm (39%) at mid

23

intervention, 136ms (28% from baseline) during post-intervention, and 105ms (44%
from baseline) 7-week follow-up.
Step width diminished an increasing trend throughout the study (Figure 7). At
baseline, step width was at .2m and increases in step width of .26m (30%) during mid-
intervention,.27m (35% from baseline) during post-intervention, and.34m(70% from
baseline) during follow-up intervention. However, stride length had a decreasing trend
throughout the study (Figure 8). At baseline, stride length was at .91m and decreases
to.75m (17%) during mid-intervention,.68m (25% from baseline) during post-
intervention, and .74m(18% from baseline) during follow-up intervention.

24

Figure 1. Hip kinematics for particpant 1.

Figure2. Knee kinematics for particpant 1.
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25

Figure 3. Ankle kinematics for particpant 1.

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Degree (
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26

Figure 4. Stance and swing % for particpant 1.

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27

Figure 5. Velocity for particpant 1.

Figure 6. Cadence for particpant 1.

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Figure 7. Step width for particpant 1.

Figure 8. Stride length for particpant 1.

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Participant 2
Participant 2 was a 14 year old girl with left sided mild spastic hemiplegia;
GMFCS level I and experiences walking characteristics of left toe walking. Participants
medical history consisted of tibial osteotomy of the left lower extremity 6 years prior to
this study.
At baseline, hip kinematic graph during pre-intervention displayed an early and
excessive hip flexion that occurs during terminal stance and pre-swing phase of
participants gait cycle (Figure 9). Hip flexion was then decreased and occurs later during
mid and post intervention. However, hip flexion did not retain its effect during follow-up
intervention. There were no other systematic changes in knee and ankle kinematics
observed throughout gait cycle (Figure 10 & Figure 11).
Stance and swing phase, velocity, cadence, and stride length showed fluctuation
throughout intervention (Figure 12 Figure 14 & Figure 16). However, step width show
a decreasing trend pre and mid- intervention at .17m to.1m (41%) post intervention, and
retaining its effect at .12m (29% from baseline) follow-up (Figure 15).

30

Figure 9. Hip kinematic for participant 2.

Figure 10. Knee kinematic for participant 2.
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Figure 11. Ankle kinematics for participant 2.

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32

Figure 12. Stance and swing% for participant 2.

0%20%40%60%80%100%
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Figure 13. Velocityfor participant 2.

Figure 14. Cadencefor participant 2.

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Figure 15. Step widthfor participant 2.

Figure 16. Stride length for participant 2.

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35

Participant 3
Participant 3 was a 7 year old girl with left sided mild hemiplegia, GMFCS level I
and experiences walking characteristics mild hemiplegic gait. Participants secondary
diagnosis was asthma and had no other related medical history.
At baseline (pre-intervention), hip, knee, and ankle kinematic displays an early
and excessive hip extension, knee flexion, and limited plantar flexion during terminal
stance and pre-swing of participants gait cycle (Figure 17-19). However, after mid and
post intervention, hip extension, knee flexion decreased but did not retain its effects 7
weeks follow-up intervention. Additionally, plantar flexion increases mid and post
intervention but did not retain its effect during 7-week follow-up.
Stance phase showed increasing trend throughout the study and adversely effects
swing phase of the participants gait cycle (Figure 20). At baseline, stance phase was at
56% and increase to 64% (14%) during mid-intervention, 68% (21% from baseline)
during post-intervention, and a slight decrease from mid-intervention to follow-up
intervention but still show an increasing trend from baseline at 62% (10%) stance phase.
Velocity decreased progressively from .92ms to .7ms (24%)pre to post
intervention, however increased follow-up intervention to .81ms (Figure 21). Cadence
also decreased progressively from 113sm to 97sm (15%) pre to post intervention,
however increased during follow-up intervention to 107sm (Figure 22).
Step width decreased from .13m to .05m (58%) pre to post intervention (Figure 23).
However, step width did not retain its effect during follow-up intervention and increasing

36

to .17m (30%). There was no systematic change in stride length (Figure 24).

37

Figure 17. Hip kinematics for participant 3.

Figure 18. Knee kinematics for participant 3.
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Figure 19. Ankle kinematics for participant 3.

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39

Figure 20. Stance & swing % for participant 3.

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Figure 21. Velocity for participant 3.

Figure 22. Cadence for participant 3.

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Figure 23. Step widthfor participant 3.

Figure 24. Stride lengthfor participant 3.

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Participant 4
Participant 4 was a 10 year old boy with mild spastic diplegia, GMFCS level II-
III. According to participants physical therapist, left side was mostly affected and
experiences walking characteristics of equinus and stiff knee gait. Participants medical
history consisted of left femoral osteotomy, bilateral tibialostetomy, bilateral hamstring
lengthening, and bilateral adductor tenotomy, all within 3 years prior to this study.
There were no systematic changes in hip kinematics for participant 4 (Figure 25).
At baseline, knee kinematics displayed an increase in knee flexion during initial swing
and mid swing from pre to mid intervention and continues to maintain effect through
follow-up intervention (Figure 26). Ankle kinematics displayed a reduction of unwanted
plantar flexion from pre to mid intervention during pre-swing and initial swing and
continued to maintain its effect through post intervention (Figure 27). However, during
follow-up intervention, plantar-flexion excessively increased more than baseline data
collection.
Stance and swing phases, velocity, cadence, and stride length showed fluctuation
throughout the intervention (Figure 28 Figure 30 & Figure 32). However, step width
had an increasing trend from mid through follow-up intervention (Figure 31). At mid-
intervention, step width was at .08m and increases to.12m (9% from mid-intervention)
during post-intervention, and.13m (18% from mid-intervention) during post-intervention.

43

Figure 25. Hip kinematics for participant 4.

Figure 26. Knee kinematics for participant 4.
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Figure 27. Ankle kinematics for participant 4.

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Figure 28. Stance & swing % for participant 4.

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46

Figure 29. Velocity for participant 4.

Figure 30. Cadence for participant 4.

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Figure 31. Step width for participant 4.

Figure 32. Stride length for participant 4.

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48

DISCUSSION
The purpose of this study was to investigate the effects of a 6-week aquatic group
exercise program on gait outcomes in children with CP. It was hypothesized that the 6-
week aquatic intervention would improve hip knee and ankle kinematics as well as
spatial temporal variables (velocity, cadence, stance and swing phase, stride length, and
step width).
Participant 1 revealed no characteristics of crouch gait in hip joint during this
study. However, slap foot was noticeable during participants pre-intervention evaluation.
Slap foot typically occurs when the person's pretibial muscles (particularly the anterior
tibialas) are weak and the individual does not have the strength to control the slowing
down effect of plantar flexors during initial contact and loading response at the beginning
of the gait cycle (Perry, J. &Burnfeild, 2010). Aquatic exercise may have increased in
strength of the participant's anterior tibalis muscle due to a smoother heel rocker
transition in plantar flexion during initial contact at mid intervention and was maintained
throughout post and 7-week follow up intervention (Figure 3).
Although velocity decreased in accordance to hisher step length decreasing,
participant 1 displayed wider steps when walking and emphasizing on a much wider base
of support (Figure 7). Eek et al. (2008) suggested that increase of base of support during
walking increases stability in stance phase during gait cycle and makes it easier for the
ankle plantar flexors to push off actively. Our findings indicate that aquatic exercise can
help facilitate how to walk properly with an appropriate base of support which helps with
hisher slap foot during initial contact. In addition, Liao et al. (2007) states that the

49

benefit of a muscle strengthening program on gait speed depends on the targeting specific
muscles, in which this present study was not specifically designed for. The present study
targeted walking ability as a whole and concentrated on walking ability for each
individual. Although there was no test that the participant was cognitively aware of their
walking ability, the decrease in velocity with a much wider base of support during
walking can be assumed that the participant was a lot more careful in her walking
throughout the intervention.
Participant 2 had tibial osteotomy, where surgical procedure takes place when the
distal end of tibia and is severed on the lateral (open wedge osteotomy) or medial
(closing wedge osteotomy) of the tibia to realign the angles of the lower leg. Participant's
tibialosteotomy 6 years prior to this study have decreased alignment in the frontal view.
However, this present study looked at sagittal plane kinematics. The participant's regular
standing stance favored the right side due to pain and weakness on the participant's
contracted plantar-flexed left foot. Favoring all of her weight onto the right side, the left
foot is plantar flexed during her regular standing posture as well as during walking. Perry
et al. (2010) states, individuals with muscle weakness can modify the timing of muscle
action to avoid threatening postures and induce protective alignment during stance. An
increased plantar flexion may have had an exaggerated hip and knee flexion during mid-
swing of the gait cycle for the foot to clear during mid-swing, which is demonstrated in
her kinematic graphs (Figure 9 & Figure 10). The added flexion can carry over into
terminal swing but would not persist as the limb approached the floor, in which this
participant experiences. Our outcomes indicate that hip and knee flexion decreased and
was retained post intervention. However, 7-week follow-up, hip flexion and knee flexion

50

increased over time. This present study illustrates that aquatic exercises have improved
walking ability by possibly strengthening the participant's hamstrings that might have
countered the rapid hip and knee flexion during mid-swing.
All other spatial-temporal variables measured for participant 2 displayed
fluctuations throughout the intervention except for a decreasing trend in step width. In
this particular case, the participant's age had passed the participant's growth spurt.
Although maturation may improve a child's developmental growth, it may also affect it
adversely. Development not only affects treatment of these children but also may
complicate measurement of treatment outcomes. Therefore, there were no trends in the
participant's spatial temporal variables due to her development. However, the participant
presented a trend in decreasing the step width pre to post intervention and retaining its
effects (Figure 15). In contrast to participant 1 and their increase in step width, participant
2 showed a decrease in their base of support in their walking indicating an effect of
improving their balance while walking. Narrowing base of support can imply an
improvement in balance systems in deviated walking which shows in this present study.
Participant 3, after baseline data, display normal ranges in hip, knee, and ankle
kinematics at mid to post intervention (Figure 17-19). However, the changes did not
retain during follow-up intervention. In this case, aquatic exercise may have increased
gains in muscular strength in all muscle groups that assists in a persons walking ability.
It appears that the participant developed an effective way of clearing the leg during the
swing phase by decreasing hip extension, knee flexion, and increasing plantar flexion.
Additionally, typical gait cycle consists of 60% stance phase and 40% swing phase.

51

Participant 3 displayed an increase in stance phase during the gait cycle and reached
ranges of typical gait cycle phases (Figure 20). However, the participant did not retain its
effect during follow-up intervention.
Participant 4 showed an excessive plantar flexion during pre to initial swing
possibly due to his jump knee and equinus gait in which the participant experiences
muscle tone and spasticity. The participants foot did not seem generate enough strength
to clear the ground and into dorsiflexion (Figure 27). Equinus gait can be observed as
initial swing that causes tripping as advancement of the limb is delayed. Perry et al.
(2010) states that if the foot cannot reach its forward position to receive the advancing
body weight, the subject will fall. With an increase in plantar flexion during swing phase,
excess knee flexion would have to occur for the whole leg to propel through the swing
phase of the gait cycle. Overall, aquatic exercise has contributed to an increase in strength
of the anterior tibialas muscle. Thus, decreasing the amount of plantar flexion used to
clear the ground, and decreasing the amount of knee flexion used during pre to initial
swing phase. In addition, parents of this participant stated that the participant did not rely
on assistive device on transportation and was able to walk with decreased fall
incidences.

52

CONCLUSION
Aquatic therapists and clinicians in rehabilitation can use our findings when
utilizing an aquatic exercise program for populations with CP or other similar
neurological disorders. Clinicians are encouraged to incorporate the use of aquatic
exercise program to their gait rehabilitation regimen for children with CP. Overall,
exercise and physical activity are beneficial for children with and without disability to
promote health. The use of an aquatic environment can be an alternative source to getting
children with disabilities more physically active, which can prevent obesity and other
complications associated with inactivity. Due to the nature of this preliminary case study,
we suggest that future studies should involve a randomized control study with a larger
sample size. In addition, Gross Motor Function Measure (GMFM) can be used to
correlate gait outcomes in future studies.
In summary, our case study outcomes suggest that group aquatic exercise can be
beneficial for children with mild to moderate CP. Our findings also suggest that the
effects of aquatic exercise may vary from individual to individual considering the large
variability of physical conditions among children with CP. Clinicians can take such
individualizing into consideration as they develop aquatic exercise programs for children
with CP.

53

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APPENDIX A

MEDICAL RELEASE FORM
Name of Client: ______________________________________________________ DOB__________
(Print) Last Name First Name
To: Attending Physician
The Center of Achievement for the Physically Disabled is designing an exercise program for your patient.
The program may include exercises for improved muscular strength, range of motion, cardiovascular
endurance, posture and balance.
The Center of Achievement requests that you provide any medical information, which would affect the
selection of activities. All medical records will be handled in strict confidence. Thank you for your
assistance.Please complete items I, II, & III below as applicable:
I. Primary Physical Disability:
_______________________________________________
Secondary Medical Diagnosis: _____________________________________________
II. Client is medically cleared for the following program(s):
Land Based Exercise Aquatic Based Exercise Both Land Based & Aquatic None

Patient IS NOT CLEAREDfor the following
exercises:LAND BASED EXERCISE PROGRAM
Patient IS NOT CLEARED for the following
exercises:AQUATIC BASED EXERCISE PROGRAM
No Strength Training Exercises No Strength Training Exercises
No Partial Weight Bearing (i.e. tilt table) No Assistive Weight Bearing
No Stretching Exercises ActivePassive No Stretching Exercises ActivePassive
No Cardiovascular Exercise No Cardiovascular Exercise
No Submersion
No Deep Water Exercise
III. Please give a brief explanation for above restrictions andor your recommendations.(Example
Max Working Heart
Rate)_________________________________________________________Physicians Signature:
_______________________________________, M.D. Date: ___________ Print Name:
_______________________________Phone: (___)_____________ FAX: (___)________
18111 Nordhoff Street, Northridge, CA 91330-8287
Phone (818) 677-2182 Fax (818) 677-3246
Reviewed by _________

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APPENDIX B
California State University, Northridge
CHILD ASSENT TO BE IN A HUMAN RESEARCH PROJECT
Effects of Aquatic Exercise on Gait and Balance in Children with Cerebral Palsy
This paper explains a research project. The people doing the research would like your
help, but they want you to know exactly what this means. Participating in this project is
your choice. Please read about the project below. Feel free to ask questions about
anything that you do not understand before deciding if you want to participate. A person
connected to the research will be around to answer your questions.
Informal Title of the study How water exercise can help you walk and stand better
Formal Title: Effects of Aquatic Exercise on Gait and Balance in Children with Cerebral
Palsy
RESEARCH TEAM
Name and Title of Researcher: Robert De La Cruz, Graduate Teaching Assistant
Department: Kinesiology
Telephone Number: (818) 677-2182
Name and Title of Faculty Advisor:Dr. Taeyou Jung
Department: Kinesiology
Telephone Number: (818) 677-2182
Study Location(s): Center of Achievement through Adapted Physical Activity,
California State University, Northridge
YOU ARE HERE BECAUSE.
We want to study how water exercise can help you walk and stand better. We want to
see if you would like to be in our study.

58

WHY ARE THEY DOING THIS PROJECT?
Dr. Jung, Mr. De La Cruz, and some other researchers are doing this research project to
learn more about how the pool exercises might help you stand and walk better.
WHAT WILL HAPPEN IN THE PROJECT?
These things will happen if you want to be in the study:
1.) When you say yes to help us, you will be asked to do exercises at home or in the pool
3 times a week for 12 weeks. Before and after the 12 weeks of exercise, you will be
tested for standing and walking.
2.) When you come to our center for our study, you will be asked to stand still on a
square metal plate for the standing test and walk on a path a few times for the walking
test. We will tell you more about what to do when you get to the center.
3.) When you are doing the standing test, you will wear a safety vest to make sure you do
not fall. You will be asked to stand still on the metal plate while you are given directions
such as closing your eyes or moving your body from side-to-side. During some of the
tests, the plate that you are standing on might wobble. The computer will trace how your
body moves while you are trying to stand still. You will be able to sit down and rest after
each test.
4.) When you are tested for walking, you will be asked to change into tight fitting bike
shorts. We will measure how tall you are, how much you weigh, and how youre your
legs are. Shiny stickers will be put on your skin. You will be asked to walk on a path a
few times while the cameras record your walking. You will be able to sit down to rest
after each time you walk.
5.) If you are told to exercise in the pool, you will workout for 40-minutes in the water 3
times a week for 12 weeks. You will do some stretching, walking, standing exercises,
and fun games. A teacher and a lifeguard will be there to help you.
6.) If you are told to exercise at home, you will workout for 40-minutes at home with
your parentguardian 3 times a week for 12 weeks. You will do some stretching,
walking, standing exercises, and fun games with your parentguardian.
You might feel bored, tired, thirsty, and pain in your legs andor chest. Before you do
any of the exercise, your doctor will need to say that it is okay for you to exercise. You
will have breaks to rest will be asked to drink plenty of water to keep you from being
thirsty.

59

IF YOU HAVE ANY QUESTIONS
You can ask questions any time. You can ask now or you can ask later. You can talk to
the researchers, your family or someone else in charge. It is important that you know
what is going on.
DO YOU WANT TO BE IN THE PROJECT?
No
You do not have to be in the study. No one will be upset with you if you don't want to do
this. If you don't want to be in this study, or if you want to skip a question that is hard or
confusing, thats fine. Just tell the researchers and they wont get upset.
Yes
If you want to be in the study sign your name below. You can say yes now and say no
later. It is up to you to decide.

Signature of Child Age Date

Signature of Researcher Date

Signature of Individual Obtaining Assent Date
If different from researcher

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