The Effects of Strengthening Programs on
Independence on Individuals with Down Syndrome:
A Case Report and Evidence Based Analysis
Jessica Seeley
Physical Therapy Doctorate Program
Class of 2013
University of New Mexico School of Medicine
Advisor:
Beth M. Jones, PT, DPT, OCS
Table of Contents
Abstract .............................................................................................................................................................. 2
Section 1: Background and Purpose ................................................................................................................. 3
Section 2: Case Description ............................................................................................................................... 5
Section 3: Evidence Based Analysis .................................................................................................................. 14
Discussion .......................................................................................................................................................... 32
Conclusion .......................................................................................................................................................... 33
References ......................................................................................................................................................... 34
Tables and Figures ............................................................................................................................................. 36
Appendix ............................................................................................................................................................ 39
1
Abstract
Background/Purpose: Individuals with Down syndrome generally have deficits in motor skills and
decreased strength throughout development. There are several strengthening interventions that can be
beneficial for improving the decreased strength and motor skills including progressive resistance training,
treadmill training, and balance and agility training. The purpose of this case study and evidence-based
analysis was to determine the effect that various strengthening interventions can have on the level of
independence and potentially quality of life for individuals with Down syndrome.
Case Description: The patient was a 23-month-old female diagnosed with Trisomy 21, as well as acute
myelogenous leukemia. She had decreased strength and overall gross motor delays.
Outcomes: Following various strengthening interventions of 8 randomized controlled trials, the
experimental groups showed significant improvements in upper and lower-limb muscle strength, as well as
improved balance and agility as compared to the control groups.
Discussion: After performing an extensive database searches and research article analyses, it was
determined that various strengthening interventions can lead to significant improvements in upper and
lower-limb muscle strength, as well as improved balance and agility were observed in individuals of all ages
with Down syndrome. Therefore, progressive resistance training, treadmill training, and agility training are
interventions that can be used in the clinic to promote strengthening and allow for improved functional,
social, and vocational independence for individuals of all ages with Down syndrome.
2
SECTION 1: Background and Purpose
Each year, 1 in every 660 babies is born with Down syndrome in the United States Individuals with
Down syndrome generally have deficits in motor skills and decreased strength throughout their
development and lifespan5. Infants and children with Down syndrome are typically slower to reach
developmental milestones such as sitting, standing, creeping and walking1. Young children learn through
interaction with their environment, which requires the ability to move and freely explore their surroundings.
Therefore, the delays in gross motor development can decrease their independent functional mobility, play
and social interaction. For adolescents and adults, these deficits can negatively impact social and
vocational development, as typically their workplace activities emphasize physical rather than cognitive
skills8.
During a clinical rotation at the University of New Mexico Hospital, physical therapy was provided
to a young girl who inspired investigation into this case study and evidence-based analysis. The patient
was a 23-month-old female diagnosed with Trisomy 21, as well as acute myelogenous leukemia. She had
decreased strength and overall gross motor delays. Inpatient physical therapy interventions focused on
developmental milestone acquisition/skills, positioning and handling, and family/caregiver education. Direct
intervention included activities and exercises for trunk stability and strengthening, bilateral lower extremity
strengthening, transitional movements, unsupported standing and cruising along stable objects. Due to the
inpatient setting, there was limitation to the types of interventions that could be provided to this patient,
however, interest and curiosity grew as to what types of interventions could be beneficial for her and for
future patients with Down syndrome that could be referred to physical therapy. Due to the prevalence of
Down syndrome, it is important as a clinician to be familiar with and understand the evidence-based
interventions that can provide beneficial outcomes for individuals of all ages who have this diagnosis.
3
There are several strengthening interventions that can be beneficial for improving decreased
strength and motor skills, which are typically exhibited in these individuals. Such interventions used include
progressive resistance training3, ,8 treadmill training2,9,10, and balance and agility training4. However, these
specific interventions often times are not implemented in various rehabilitation setting. Some clinicians are
unaware of the vast amount of research that has been conducted on the effects of these strengthening
interventions for this population. Strengthening programs are commonly used in the rehabilitation setting for
individuals of all ages without Down syndrome, but are often overlooked or forgotten about for individuals
with Down syndrome.
The purpose of this case study and evidence-based analysis was to answer the following PICO
question: Will strengthening interventions increase the level of independence in individuals with Down
syndrome? To determine this, evidence-based exploration will be conducted through extensive database
searches and research article analyses.
4
SECTION 2: Case Description
The setting for this case study was inpatient acute care, in the pediatrics department, at the
University of New Mexico Hospital. The medical diagnosis that was the focus of this case was Down
syndrome. Physical therapy evaluation and treatment was ordered for the duration of the patient’s acute
care admission, in order to address her overall gross motor and developmental delays.
EXAMINATION: History, Systems review, and Tests & Measurements
The patient was a 23-month-old female diagnosed with Down syndrome. She was also diagnosed
with acute myelogenous leukemia in April of 2012. Her past medical history included seizure disorder,
hypothyroidism and status post AV canal repair. She was admitted to the University of New Mexico
Hospital for her AAML0431 protocol with continuous infusion of cytarabine and etoposide. She tolerated the
protocol well with some intermittent fevers.
Past Medical History
•
Down syndrome.
•
Acute Myelogenous Leukemia; which was diagnoses in April of 2012. She was on chemotherapy
protocol AAML0431.
•
Status post arteriovenous canal repair at 5 months of age.
•
Hypothyroidism.
•
History of myoclonic seizures; it was documented that they are well controlled.
•
Known documented allergies: lisinopril and losartan.
Social and Family History
The patient’s mother provided report of the patient’s social and family history. The patient lived with
her mother in Santa Fe. Her parents were divorced, but the father was still involved. Other family members,
5
including her grandmother, are also very involved in the patient’s life and with her daily and medical care.
The patient was an only child and did not currently attend daycare. There were home nurses that visited the
home and took care of the patient when her mother was working. Mother stated that the patient was a very
happy and active child at home. The patient engaged in social interaction and play with family members
and other individuals, as evident by observation and mother’s report.
Patient’s Values
During the initial evaluation, the patient’s mother expressed a strong family value and said that she
was very involved in the patient’s multidisciplinary care. The mother was very proactive and sought out the
ways to best improve the patient’s well being. The mother was very receptive to physical therapy
interventions and education for the patient during her admission, as well as for when the patient was
discharged back home.
Goals & Expectations
The patient’s mother reported that her goals for the patient were to improve her functional abilities,
including standing on her own and cruising along furniture. She also stated that she wanted the patient to
be able to play more independently at home. Additionally, the patient’s mother had inquired about what she
could to do, in conjunction with physical therapy, to improve the patient’s development during the inpatient
admission, and once they were discharged back home to Santa Fe.
Systems Review: An overview of systems review was determined through an extensive chart review,
mother’s report at the time of evaluation, and patient observation/examination.
•
GENERAL: Fevers and fussiness were noted in the chart. Mother reported that there were no
recent weight changes.
•
EYES/EARS/NOSE/THROAT: There was no eye drainage, ear pain, complaints of a sore throat or
nasal congestion were reported or observed.
6
•
RESPIRATORY: No coughing, shortness of breath or wheezing reported or observed.
•
CARDIOVASCULAR: No palpitations or chest pain were reported or observed.
•
GASTROINTESTINAL: Positive for vomiting as listed in the chart. No report of diarrhea or
constipation. The patient does have some history of gas.
•
GENITOURINARY: No frequency or urgency problems, as well as no foul-smelling urine were
reported or observed.
•
SKIN: No new rashes, lesions or discoloration on the skin were reported or observed.
Test and Measures
•
Musculoskeletal Assessment: Musculoskeletal range of motion was observed and assessed for
bilateral upper and lower extremities.
o Right Upper Extremity: within functional limits.
o Left Upper Extremity: within functional limits.
o Right Lower Extremity: within functional limits.
o Left Lower Extremity: within functional limits.
•
Posture & Alignment: Upon observation, the patient’s feet tended to pronate while she was in a
supported standing position. The fourth toe tended to adduct and lie underneath the third toe. This
presented bilaterally.
•
Functional Movements and Abilities: The patient’s functional ability and mobility was observed
during the evaluation in prone, sitting and standing positions. Observations were also made as to
the patient’s abilities and limitations with functional movement transitions.
o Prone: Patient would creep up on her hands and knees with a reciprocal pattern. Her hips
were slightly abducted while in a quadruped position.
7
o Sitting: Patient tucked her chin with pull to sit movement. She sat independently for
extended periods of time. Patient was able to maintain a straight back and hold her head
up at 90° while sitting unsupported, playing with toys.
o Standing: Patient stood next to the crib rail without support. Her knees occasionally went
into hyperextension. Both feet were pronated but not severely. Patient was just beginning
to be able to cruise along furniture with some support.
o Transitional Movements: Patient transitioned from supine and prone into a sitting position.
She also moved well from sitting into a quadruped position for reciprocal creeping. She
transitioned to standing with minimal assistance during the PT evaluation. Her mom
reported that she would pull to a standing position on her own at home.
•
Muscle Tone & Strength: The patient’s muscle tone was overall hypotonic, as evident by
palpation, passive range of motion, and observation of posture and stability in various positions.
Through observation of functional mobility and functional transfers, it was determined that she had
overall decreased strength in bilateral upper and lower extremities.
•
Fine Motor Skills: The patient demonstrated a pincer grasp with the right and left hand when
picking up smaller toys.
EVALUATION: Clinical judgments based on examination
Diagnosis
•
Medical Diagnosis: Trisomy 21; Diagnosis Code: 758.0
•
Physical Therapy Diagnosis: Decreased gross motors skills and developmental delays.
Narrative Assessment
The patient was a 23-month-old female diagnosed with Down syndrome. She was also diagnosed
with acute myelogenous leukemia in April of 2012. Other past medical history included hypothyroidism, and
8
seizure disorder. The patient was status post arteriovenous canal repair at the age of 5. During the physical
therapy evaluation, she was sitting independently for extended periods of time. She was also creeping on
hands and knees with a reciprocal pattern. The patient could pull to stand with minimal assistance, but her
mom stated that she would pull to stand on her own at home. She also had overall decreased strength of
her extremities and was unable to cruise independently along furniture. She demonstrated overall gross
motor and developmental delays for her age due to decreased strength and hypotonicity. After evaluation
and observation, it was determined that she was functioning at around an 11 to 12 month old age level. The
patient was motivated to participate in therapy activities and also had supportive family that was often
present for therapy sessions. She had a good prognosis to benefit from physical therapy interventions to
improve her strength and stability, transitional movements, and overall functional mobility.
Problem List
The patient presented with impairments and functional limitations that are typically seen in children with
Down syndrome. In addition, the patient’s diagnosis of acute myelogenous leukemia and previous hospital
admissions could have also contributed to the gross motor impairments and limitations that were observed.
The following problem list was determined after the initial physical therapy evaluation and subsequent
therapy sessions:
•
Impairments:
1. Patient had gross motor and developmental delays.
2. Patient had decreased strength in bilateral upper and lower extremities..
3. Patient had overall hypotonicity.
•
Functional Limitations:
4. Patient was unable to pull to stand independently, due to decreased strength and hypotonicity.
9
5. Patient was unable to cruise along her crib rail independently, due to decreased strength and
hypotonicity.
Physical therapy recommendation for the anticipated discharge destination was for the patient to return
home with family care. It was also recommended that she receive evaluation and treatment through an
Early Intervention program at home to continue progressing with her gross motor skills.
Short Term Acute Care Goals
1. Patient will pull to stand independently at crib rail 3 out of 4 trials, in 2 weeks.
2. Patient will cruise 4ft in each direction, while holding onto her crib rail, in 2 weeks.
Long Term Acute Care Goals
1. Patient will stand independently for 1 minute, with contact guard support, in 4 weeks.
2. Patient will cruise 4ft, with supervision assist, in 4 weeks.
Plan of Care
It was determined that the patient would receive inpatient physical therapy 2-3 times per week
throughout her acute care admission. She was admitted to the University Hospital for approximately 10
days, and was seen by physical therapy for an evaluation and treatment sessions 4 times.
Prognosis
The patient was happy and motivated to participate in therapy activities and play. She also had
very supportive and involved parents and family members. Family was present and very engaged in the
therapy sessions. Due to these factors, the patient had a good prognosis for improving her gross motor
skills with physical therapy intervention.
INTERVENTIONS
The patient was seen by physical therapy throughout her inpatient admission for developmental
exercises. Physical therapy interventions focused on developmental milestone acquisition/skills, positioning
10
and handling, and family/caregiver education. Direct intervention included activities and exercises for trunk
stability and strengthening, bilateral lower extremity strengthening, transitional movements, unsupported
standing and cruising along stable objects or furniture.
Physical Therapy Evaluation:
During the evaluation, the patient was assessed for musculoskeletal active and passive range of
motion in bilateral upper and lower extremities and overall muscle tone. Her functional abilities and/or
limitations were assessed in prone, sitting, and standing positions, as well as with transitional movements.
During the evaluation of these areas, therapeutic interventions were also performed on the patient. Gentle,
passive stretching into supination was performed on feet bilaterally, in sitting and supine positions. The
patient then worked on pull to sit and spent time in unsupported sitting while using bilateral upper
extremities to reach for and play with various toys. She was then assisted into standing at the rail of her
crib. Physical therapist worked on assisting her with standing in this position without her knees going into
hyperextension.
The patient’s mother and grandmother were both present during the evaluation. They were
educated on what the physical therapy plan of care would be throughout the remainder of her admission.
Family was also educated on ways to assist the patient with developmental activities, outside of therapy
session times.
Physical Therapy Session #1:
The patient worked on creeping in order to retrieve toys to play with, she tended to half creep
and/or scoot herself along at times. She worked on pulling to stand and stood next to furniture for extended
periods of time. The patient worked on standing without hyperextension of her knees. Her feet still tended
to pronate, but the alignment looked better today than when she was standing in the crib during the
evaluation. Her mother and grandmother were educated and instructed on how to assist the patient in
standing, while supporting at her knees to prevent hyperextension.
11
Educational materials were also provided to the patient’s mother on various activities and exercises
to facilitate gross motor development. PT discussed and demonstrated the information that was provided to
the family. Additionally, educational materials, as well as two published articles were provided to the
mother. These materials discussed information on the effects of foot orthoses for foot pronation in children
with Down syndrome
Physical Therapy Session #2:
The patient worked on unsupported sitting at the beginning of the session, while engaging in
activities and playing with toys. To further encourage trunk stability and strengthening, the toys were held
out in front of her at various positions for her to reach for and retrieve with bilateral upper extremities. She
practiced sit to stand transitions several times at the rail of her crib, with minimal assistance. The patient
stood for 5 minutes while holding onto the crib rail and would initiate a bouncing motion, weight bearing
equally through bilateral lower extremities. PT supported at her knees to inhibit hyperextension while she
was in this standing position. She initiated cruising two steps to the left along her crib rail, with support from
therapist at her hips.
Physical Therapy Session #3:
The patient worked on transitioning from sitting to quadruped and then would creep on hands and
feet with a reciprocal pattern, for a distance of 5 feet to retrieve various toys. She would initiate reaching for
the toys with alternating upper extremities while in the quadruped position. The patient also transitioned
from sitting to standing at crib rail with contact guard assist. She was given minimal assist to keep her
knees from hyperextending in standing. She stood for extended periods of time while weight bearing evenly
through lower extremities. She continued to have slight bilateral foot pronation, but demonstrated overall
improved alignment in standing. The patient was then prompted through the use of toys and her mom to
cruise along the bed rail. She took two steps two the left and to the right, with minimal assistance at the
pelvis and bilateral knees.
12
Outcomes:
Physical therapy services were terminated because the patient was discharged from her inpatient
stay once she had finished her acute myelogenous leukemia treatment protocol. Physical therapy was
ordered and provided for the duration of her admission. The physical therapy goals that were set for the
patient were not achieved, due to her discharge prior to the anticipated time frame for achieving the goals.
However, the patient was progressing towards achieving each of the goals. She had made improvements
with developmental and gross motor skills, as well as functional mobility. Inpatient physical therapy
recommended that the patient be discharged to home with family care, and be evaluated and treated by an
Early Intervention program at home. The patient would benefit from continued physical therapy at home to
achieve further improvements and continue with her gross motor skills development.
13
SECTION 3: Evidence Based Analysis
Methodologies of Search
A comprehensive evidence-based literature search was performed to find research studies related
to strengthening interventions for individuals of all ages with Down syndrome. Searches were performed
using PubMed, CINAHL Plus, and PEDro databases (Table 1).
•
For the PubMed database, an advanced search was performed including the following keywords:
o [Title Field]: Down syndrome (AND)
o [All Fields] Different combinations of:

Strength training, resistance training, treadmill training, agility training,
strengthening, and exercise.
o These searches yielded 202 articles.
•
For CINAHL Plus database, an advanced search was performed including the following keywords:
o [TI Title]: Down syndrome (AND)
o [TX All Text]: Different combinations of:

Strength training, resistance training, treadmill training, agility training,
strengthening and exercise.
o These searches yielded 97 articles.
•
For the PEDro database, an advanced search was performed including the following keywords:
o [Abstract & Title]: Down syndrome (AND)
o [Therapy]: Strength training
o [Therapy]: Fitness training
o [Title Only]: Treadmill Training
o [Title Only]: Exercise
•
These searches yielded 48 articles.
14
Evidence-Based Research Articles
The following 8 research articles were reviewed and analyzed:
1. Shields N. and Taylor NF. A student-led progressive resistance training program increases lower limb muscle
strength in adolescents with Down syndrome: a randomized controlled trial. Journal of Physiotherapy. 2010;
56:187-193.
2. Shields N, Taylor NF, Dodd KJ. Effects of a community-based progressive resistance training program on
muscle performance and physical function in adults with Down syndrome: a randomized controlled trial. Archives
of Physical Medicine and Rehabilitation. 2008; 89:1215-1220.
3. Lin H-C, and Wuang Y-P. Strength and agility training in adolescents with Down syndrome: A randomized
controlled trial. Research in Developmental Disabilities. 2012; 33: 2236-2244.
4. Gupta S, Rao BK, SD K. Effect of strength and balance training in children with Down syndrome: a randomized
controlled trial. Clinical Rehabilitation. 2011; 25: 425-432
5. Rimmer JH, Heller T, Wang E, Valerio I. Improvements in physical fitness in adults with Down syndrome.
American Journal on Mental Retardation. 2004; 109(2):164-174.
6. Carmeli E, Kessel S, Coleman R, Ayalon M. Effects of a treadmill walking program on muscle strength and
balance in elderly people with Down syndrome. Journal of Gerontology: MEDICAL SCIENCES. 2002; 57A(2):
M106-M110.
7. Ulrich DA, Ulrich BD, Angulo-Kinzler RM, Yun J. Treadmill training of infants with Down syndrome: evidencebased developmental outcomes. Pediatrics. 2001;108(5). DOI:10.1542/peds.108.5.e84.
8. Ulrich DA, Lloyd MC, Tiernan CW, Looper JE, Angulo-Barroso RM. Effects of intensity of treadmill training on
developmental outcomes and stepping in infants with down syndrome: a randomized trial. Physical Therapy.
2008; 88(1):114-122.
15
Research Article #1
Shields N. and Taylor NF. A student-led progressive resistance training program increases lower limb
muscle strength in adolescents with Down syndrome: a randomized controlled trial. Journal of
Physiotherapy. 2010; 56:187-193.
Level of Evidence (Oxford scale): 1b
Purpose: To determine whether a progressive resistance training (PRT) program leads to increased
muscle strength and improved physical function in adolescents with Down syndrome.
Methods: This was a random controlled trial, in which participants were randomly allocated to the
experimental or control group using a concealed method, with block randomization. Group allocation was
prepared and performed by a researcher not involved in recruitment or assessment.
•
Participants
o 23 adolescents with Down syndrome aged 13 to 18 years. Inclusion criteria: able to follow
simple verbal instructions in English, and fit and well enough to participate in the training.
o 7-item Physical Activity Readiness questionnaire was given to parents. The level of
intellectual disability of each participant was documented.
o Exclusion: participation in a PRT program in the 6 months prior to the trial.
•
Experimental Group Intervention (n = 11)
o Progressive resistance training program led by physiotherapy students, twice per week for
10 weeks. The intervention was completed at a community gymnasium.
o Consisted of 6 exercises on pin-loaded weight machines.

Three UE exercises: lat pull-down, seated chest press, seated row.

Three LE exercises: seated leg press, knee extension, calf raise.
o 3 sets of 12 repetitions, or until fatigue, with a 2-minute rest in between each set.
16
•
Control Group Intervention (n = 12)
o Participants continued with their usual daily activities, which may have included leisure and
sporting activities, but did not include a PRT program.
•
Outcome Measures
o Both groups were assessed at baseline and after the 10-week intervention phase.
o Muscle strength was assessed using 1RM chest press and leg press.

Minimally Clinically Importance Difference: 40% increase 1RM leg press
o Lower-limb physical function was measured using the Timed Up and Down Stairs test.
Upper-limb physical function was measured using the Grocery Shelving Task.
Results: The experimental group increased lower limb muscle strength compared to the control group (MD
36kg; 95% CI, 15-58; SMD 0.7). The lower limb strength increase represented a 42% increase in baseline
strength, which was clinically significant. There were no significant differences between the groups for
upper limb muscle strength or upper and lower limb physical function.
Critique & Conclusion: One of the main strengths of this study was that it was the first randomized
controlled trial to assess the affects of progressive resistance training (PRT) for adolescents with Down
syndrome. This study design also had high internal validity with random, concealed allocation of subjects to
the groups, blinding of therapists administering the intervention, and an intention to treat analysis. However,
the subjects and assessors were not blinded to which group was the experimental. Another weakness to
the study was that there was no follow-up to determine if the effects were maintained long term. The data of
this trial showed that PRT was effective in improving the strength of the quadriceps and hip extensors,
which are the two major antigravity muscles. In conclusion, this type of student-led PRT was a feasible,
safe, and inexpensive intervention option for adolescents with Down syndrome that can lead to
improvements in lower-limb muscle performance.
17
Research Article #2
Shields N, Taylor NF, Dodd KJ. Effects of a community-based progressive resistance training program on
muscle performance and physical function in adults with Down syndrome: a randomized controlled trial.
Archives of Physical Medicine and Rehabilitation. 2008; 89:1215-1220.
Level of Evidence (Oxford scale): 1b
Purpose: To determine if a community-based progressive resistance training (PRT) program improves
muscle strength, muscle endurance, and physical function in adults with Down syndrome.
Methods: This was a randomized controlled trial, in which participants were randomly allocated to either an
intervention or control group using concealed allocation, block randomization method. Participants were
assigned to their allocation by a physiotherapist not involved in the study after baseline measures.
•
Participants
o 23 adults with Down syndrome aged 20-49 years. Inclusion criteria: able to follow simple
verbal instructions in English, and fit and well enough to participate in the training.
o 7-item Physical Activity Readiness questionnaire was given to parents. The level of
intellectual disability of each participant was documented.
o Exclusion: participation in a PRT program in the 6 months prior to the trial.
•
Experimental Group Intervention (n=9)
o PRT program supervised by 2 accredited fitness trainers, twice per week for 10 weeks, at
a community gymnasium.
o Consisted of 6 exercises using weight machines.

Three UE exercises: shoulder press, seated chest press, seated row.

Three LE exercises: seated leg press, knee extension, seated calf raise.
o 2-3 sets of 10-12 reps, or until fatigue, with a 2-minute rest in between each set.
18
•
Control Group Intervention (n=11)
o Participants continued with their usual activities, which included employment, leisure and
sporting activities, but did not include a PRT program.
•
Outcome Measures
o Both groups were assessed at baseline and after the 10-week intervention phase.
o Muscle strength was assessed using 1RM chest press and leg press.
o Muscle endurance was measured by counting the number of reps completed at 50% 1RM
for the seated chest and leg press.
o Lower-limb physical function was measured using the Timed Up and Down Stairs test.
Upper-limb physical function was measured using Grocery Shelving Task.
Results: The intervention group showed significant improvement in upper-limb muscle endurance
compared with the control group (MD # of chest press reps at 50% 1RM, 16.7; 95% CI 7.1-26.2). There
was also a trend towards an improvement in upper-limb muscle strength (MD chest press 1RM, 8.6kg; 95%
CI, -1.3 to 18.5kg) and in upper-limb function (MD grocery shelving task, -20.3s; 95% CI, -45.7 to 5.2s). No
significant differences between groups for lower-limb muscle performance or physical function measures.
Critique & Conclusion: One of the main strengths of this study was that it was a randomized controlled
trial that conformed to the training guidelines of the ACSM for adults with Down syndrome. Another strength
was the high internal validity due to random, concealed allocation of subject, blinding of all assessors
measuring at least one key outcome, excellent program compliance and no withdrawals. and an intention to
treat analysis. However, weaknesses of the trial included lack of therapist blinding, relatively small sample
size of participants, as well as a short duration and lower frequency of the intervention. Overall conclusion
is that PRT in a community gymnasium was a feasible, safe, and inexpensive intervention option for
individuals with Down syndrome that can lead to improvements in upper-limb muscle performance.
19
Research Article #3
Lin H-C, and Wuang Y-P. Strength and agility training in adolescents with Down syndrome: A randomized
controlled trial. Research in Developmental Disabilities. 2012; 33: 2236-2244.
Level of Evidence (Oxford scale): 1b
Purpose: To evaluate the effectiveness of a combined strength and agility training program in adolescents
with Down syndrome, by using treadmills and Wii game protocols.
Methods: This was a random controlled trial, in which participants were randomly assigned to either the
experimental or control group using stratified random sample.
•
Participants
o 92 adolescents, aged 13-18 years currently enrolled in high school.
o Diagnosed with DS by board-certified physician, able to follower simple instructions, and
had written consent indicating agreement to participate.
o Exclusion: subjects with associated cardiovascular conditions, blindness, deafness, or
previous neurological impairments. Received PT or OT in the year preceding the study.
•
Experimental Group Intervention (n = 46)
o 6-week intervention consisting of three 35-minute sessions per week. Home programs
were not provided to the parents/caretaker to minimize possible confounding effects.
o Treadmill protocol: 5 minutes, with an average start speed of ~2.0kph and end spend
~3.0kph. The therapist determined the treatment protocol for each child in advance.
o VR: 20min Wii game-like exercise with demands for muscle strength and agility
performance. Most common chosen sports: boxing, bowling, table tennis, frisbee and golf.
•
Control Group Intervention (n=46)
o Participants continued with their normal daily activities.
20
•
Outcome Measures
o Handheld dynamometer was used to measure lower-limb muscle strength.
o Bruininks-Oserersk Test of Motor Proficiency (BOT-2) strength and agility composite (SAC)
subtests: standing long jump, push-ups, sit-ups, wall sit, and V-up, used to measure agility.
Results: Analysis between the groups revealed a significant group difference in terms of strength in all
muscle groups following the intervention. Level of significance and comparison of mean change (in pounds)
between the control and experimental group from pre and post intervention measures were as follows:
•
Hip Flexors (p = 0.010): 0.94 change in the intervention group vs. -0.08 change in the control group
•
Hip Extensors (p = 0.018): 0.64 change in the intervention group vs. 0.13 change in the control group
•
Hip abductors (p = 0.004): 1.57 change in the intervention group vs. 0.13 change in the control group
•
Knee Flexors (p = 0.029): 1.60 change in the intervention group vs. 0.17 change in the control group
•
Knee Extensors (p = 0.031): 1.42 change in the intervention group vs. 0.19 change in the control group
•
Ankle Plantarflexors (p = 0.011): 1.17 change in the intervention group vs. 0.30 change in the control group
Moderate to large effect sizes were obtained for all muscle groups as well. There was also a significant
difference found when comparing the pre-post measures on the BOT-2 SAC. (p = 0.02).
Critique & Conclusion: Strengths of this study include excellent compliance with no withdrawals, random
allocation to groups, blinding of assessors, and intention to treat analysis. However, one weakness of this
study was the lack of blinding of therapists who administered the treatment. Another weakness was the
study’s results did not generalize to group with severe and profound ID, and participants were not
monitored for other physical exercise or VR-based activities in addition to the intervention. In conclusion,
despite the limitations of this study, this type of intervention was found to be an effective, reasonable, and
relatively inexpensive intervention that can result in improvements in strength and agility for adolescents
with Down syndrome. In addition, a combination program of treadmill and VR-based activities might be
even more effective in achieving these strength and agility improvements.
21
Research Article #4
Gupta S, Rao BK, SD K. Effect of strength and balance training in children with Down syndrome: a
randomized controlled trial. Clinical Rehabilitation. 2011; 25: 425-432
Level of Evidence (Oxford scale): 1b
Purpose: To determine the effect of a strength and balance training program in children with DS.
Methods: This was a randomized controlled trial, in which the children were randomly divided into the
experimental and control group using stratified random sampling.
•
Participants
o 23 children with Down syndrome, aged 7 to 15 years
o Ability to understand simple instructions and ability to stand and walk independently.
o Exclusion criteria: associated cardiovascular condition, loss of functional vision/hearing.
•
Experimental Group Intervention (n = 12)
o Strength and balance program 3 times per week, for 6 weeks.
o Progressive resistance exercises using sandbags for lower limb: hip flexors, abductors,
extensors, knee flexors, knee extensors, and plantarflexors. 2 sets of 10 reps for each
muscle group.

Strength training was started at 50% of the 1RM.

Resistance increased by 1.1lbs when the child was able to complete the sets with
ease.
o Balance training program: Each balance activity was initially 10 performed repetitions and
increased by 5 reps when the child could do it with ease. Activities included the following:
jumps, vertical jumps, one leg stance with eyes open, tandem stance, walking on a line,
walking on a balance beam, and jumping on a trampoline.
22
•
Control Group Intervention (n=11)
o Participants continued with their activities that were being followed in the school, which
included classroom studying and play activities. .
•
Outcome Measures
o Handheld dynamometer was used to measure lower-limb muscle strength.
o
Balance subscale of Bruininks Oserersk Test of Motor Proficiency to assess balance.
Results: Children in the intervention group showed a statistically significant improvement (p<0.05) in the
lower-limb strength of all the muscle groups assessed. Level of significance and comparison of change
between the control and experimental group from pre and post intervention measures were as follows:
•
Hip Flexors (p = 0.001): 1.74 change in the intervention group vs. 0.01 change in the control group
•
Hip Extensors (p = 0.002): 2.37 change in the intervention group vs. -0.50 change in the control group
•
Hip abductors (p = 0.001): 0.95 change in the intervention group vs. -0.22 change in the control group
•
Knee Flexors (p = 0.03): 1.39 change in the intervention group vs. 0.24 change in the control group
•
Knee Extensors(p = 0.01): 2.54 change in the intervention group vs. 0.54 change in the control group
•
Ankle Plantarflexors (p = 0.02): 0.38 change in the intervention group vs. 0.22 change in the control group
There was also significant improvement in scores of the balance subscale (p = .0001).
•
BOTMP: There was a 1.0 change in the control group (8.0 pre to 9.0 post) vs. a 9.5 change in the
intervention group (10.5 pre to 19.5 post)
Critique & Conclusion: Strengths of this study included concealed, random allocation of subjects to the
groups, as well as excellent compliance to the intervention with no withdrawals. A main weakness was no
blinding of subjects, therapists or assessors. Another limitation was the small sample size. Overall, a 6week exercise training program was sufficient to signigicantly improve lower-limb muscle strength and
overall balance in children with Down syndrome. The exercise training program implemented in this study
was a safe and feasible intervention for improving strength and balance in children with Down syndrome.
23
Research Article #5
Rimmer JH, Heller T, Wang E, Valerio I. Improvements in physical fitness in adults with Down syndrome.
American Journal on Mental Retardation. 2004; 109(2):164-174.
Level of Evidence (Oxford scale): 2b
Purpose: To evaluate the effects of a combined program of strength and cardiovascular conditioning in a
cohort of adults with Down syndrome.
Methods: This was a controlled clinical trial conducted at a major university.
•
Participants
o 52 adults with DS aged 30 to 70 years. Mean age: 39.4 years.
o Eligibility criteria included: sedentary for the past year or longer, reside within a one-hour
commute of the intervention site, written permission from primary care physician, and able
to understand instructions and complete all physiological testing.
•
Experimental Group Intervention (n = 30)
o Four 12-week exercise sessions were conducted with 7 to 8 participants in each repetition.
o 30-45 min of cardiovascular exercise on one or more: recumbent stepper, stationary cycle,
treadmill, and elliptical cross-trainer. 15-20 min of muscular strength and endurance.
o 5-20 min of muscular strength and endurance. Initiated at 70% of the participants’ 1-RM for
one set of 10-20 reps, and increased by 10% when they could perform 20 reps for two
consecutive sessions with proper lifting technique.

Bench press, seated leg press, seated leg curl, triceps push-down, seated
shoulder press, seated row, lat pull-down, and biceps curl.
•
Control Group Intervention (n=22)
o Participants continued with their normal daily activities.
24
•
Outcome Measures
o Cardiovascular fitness: measured by a symptom-limited graded exercise test (peak VO2)
performed on an electronically braked upright stationary cycle, with a Metabolic Cart.
o Strength: assessed by 1-RM on the bench press and seated leg press machines. Handgrip
strength was assessed using a handgrip dynamometer.
o Body composition: skinfold measurement was taken with a skinfold caliper at the chest,
abdomen, and thigh locations for men and at triceps, suprailiac, and thigh locations for
women. The sum of the three measures was used as the actual score.
Results: There were significant gains in all measures of cardiovascular function for the treatment group’s
participants as compared to the control group. This included peak VO2, peak heart rate, time to exhaustion,
and maximum workload. (p<.01). Improvements of cardiovascular fitness ranged from 14.1% in peak VO2
to an increase of 27.1% in max workload. Significant group differences were observed for bench press and
leg press (p<.0001). Improvements in strength ranged from 39% and 43% for lower and upper-body
strength respectively. There was also a significant difference between treatment and control groups for
body weight (p<.01), but there was not a significant difference with respect to BMI or total skinfold score.
Critique & Conclusion: Strengths of this study include the large sample size of adults with DS for this
randomized controlled trial to test muscular strength and endurance, random allocation of the subjects into
groups, as well as good compliance and follow-up with the subjects. One of the main weaknesses of this
study was the lack of blinding for subjects, therapists and assessors, which could have potentially led to
bias in treatments and/or results. In conclusion, a combination of strengthening and cardiovascular exercise
was a feasible and safe intervention that can improve muscular strength and endurance in older individuals
with Down syndrome. Further research should be conducted to determine these effects with blinding of
therapists and assessors.
25
Research Article #6
Carmeli E, Kessel S, Coleman R, Ayalon M. Effects of a treadmill walking program on muscle strength and
balance in elderly people with Down syndrome. Journal of Gerontology: MEDICAL SCIENCES. 2002;
57A(2): M106-M110.
Level of Evidence (Oxford scale): 1b
Purpose: To evaluate the changes in isokinetic leg strength and balance ability and the benefits of a 6month walking program on improving leg muscle strength of elderly MR individuals with Down syndrome.
Methods: This was an RCT, in which participants were randomly assigned to groups through a coin toss.
•
Participants
o 26 individuals with Down syndrome, aged 57 to 65 years.
o All participants were residents of a foster home in Hadera, Israel for at least 4 years.
o Diagnosed with mild mental retardation, requiring minimal supervision for daily activities.
o Subjects of the study were not taking drugs, such as sedatives or narcotics, which might
have hindered balance or strength performance.
o Exclusion: pre-existing conditions that could interfere with results or lead to comorbidity.
•
Walking Group (WG) (n = 16)
o Participants walked on the treadmill three times per week, for 25 consecutive weeks.
Initially for 10 to 15 minutes as tolerated and then gradually for as long as 45 minutes.
Walked at a speed below threshold of breathlessness, but as fast as they could tolerate.

Individually prescribed low-endurance walking at 0% incline.
o Participants walked only between 9:30 and 11:30am indoors under controlled conditions.
o Heart rate, blood pressure and respiration rate were recorded before and after each
training session for monitoring purposes.
26
•
Non-walking Control Group (CG) (n=10)
o Participants were instructed not to change their current levels of physical activity.
•
Outcome Measures
o Knee extension and knee flexion strength were measured bilaterally, using a medical
isokinetic system. Data were collected for peak torque (greatest single value of 3 maximal
efforts), peak torque % body weight, and average power (expression of work per unit time).
o Dynamic balance and gait speed assessed using the TUAG test (a modification of the
Timed Up And Go). Each participant was asked to rise from an armchair, walk 6m, and
return to the chair. Target time for a good level of IND was between 26 and 30 seconds.
o 95% confidence intervals of difference were determined. The critical valued for statistical
significance was assumed at an alpha level of p < 0.05.
Results: Following the walking program, peak torque, and average power of quadriceps and hamstrings
were significantly higher than the pre-walking values. Results of the TUAG test for the WG after training
were significantly faster in comparison with pre-walking speeds. They needed 9.1% less time to complete
the test (p<0.05). All walking performances improved significantly as a result of the treadmill program.
Critique & Conclusion: One of the strengths of this study was that it was the first published study showing
a relationship between leg strength and functional ability in aged individuals with Down syndrome. Other
strengths include random allocation of subjects to groups, blinding of all assessors, participants reported
that they enjoyed the treadmill walking, and none withdrew from the study. Lastly, it was a longer
intervention of 6-months. Weaknesses included lack of blinding of subjects and therapists, which could
have led to bias in interventions and/or results. Overall, it was concluded that a regular treadmill walking
protocol led to improvements in leg strength, walking function, and balance for elderly adults with Down
syndrome, which in turn can potentially increase daily independence and improve functional capabilities.
27
Research Article #7
Ulrich DA, Ulrich BD, Angulo-Kinzler RM, Yun J. Treadmill training of infants with Down syndrome:
evidence-based developmental outcomes. Pediatrics. 2001;108(5). DOI:10.1542/peds.108.5.e84.
Level of Evidence (Oxford scale): 2b
Purpose: To test the impact of treadmill practice, administered in the homes by parents, on the rate of
onset of walking in infants with Down syndrome.
Methods: This was a 4-year randomized controlled trial, in which families of infants with Down syndrome
were randomly assigned to the intervention or control group.
•
Participants
o 30 infants with Trisomy 21 were recruited from support groups and DS clinics.
o Infants began participating in the study when they demonstrated the ability to sit
independently for 30 sec.
o Throughout the course of their participation in the study, all infants received biweekly
pediatric physical therapy.
•
Experimental Group Intervention
o Custom-engineered treadmills were placed in their homes. Parents were trained to position
their infants appropriately and implement the treadmill protocol.
o Parents administered the treadmill intervention. Infants gradually worked up to 8 minutes
per day, 5 days per week, until the infants demonstrated the ability to walk independently
(item 62 of BSID-II). Treadmill belt speed was set at .2 meters per second.
o Parents maintained a logbook and researchers visited bi-weekly, and videotaped monthly.
•
Control Group Intervention
o Did not participate in a treadmill protocol, but did receive the biweekly physical therapy.
28
•
Outcome Measures
o Motor performance was assessed with the Bayley Scales of Infant Development.
o Items monitored during each biweekly follow-up session included: raises self to standing
position, walks with help, and walks independently (3 steps).
o Parent-reported milestone achievement was also verified at each biweekly visit.
o A significance level of p = 0.05 was used for all analyses. Effect size of .5 was identified as
representing a meaningful treatment.
Results: Infants assigned to the treadmill group acquired the three behaviors faster than the control group.
•
Raises self to stand: No statistically significant difference (p = .09). Moderate effect size of (.61).
•
Walks with help: Statistically significant difference (p = .03). Large effect size statistic (.80).
•
Walks independently: Statistically significant difference (p = .02). Large meaningful effect size (.83).
o Infants in the treadmill group demonstrated the ability to walk independently 101 days
earlier than those in the control group.
o Infants assigned to the treadmill group walked on average at a chronological age of 19.9
months, while the control group walking on average at a chronological age of 23.9 months.
Critique & Conclusion: One main weaknesses of this study was the lack of blinding of subjects, therapists
and assessors, which could have led to potential bias in interventions and outcomes. Another weakness
was the decreased control of environment and protocol variability, due to the intervention taking place in
the infant’s home. However, having the intervention performed in the home allowed for the parents to be
involved in their own child’s intervention and development, which could also be considered a strength. With
training and support, parents could use treadmills in their homes to help their infants walk earlier than they
typically might. In conclusion, regularly scheduled physical therapy could be supplemented with in-home
treadmill training, performed by parents, to facilitate significantly earlier onset of independent walking.
29
Research Article #8
Ulrich DA, Lloyd MC, Tiernan CW, Looper JE, Angulo-Barroso RM. Effects of intensity of treadmill training
on developmental outcomes and stepping in infants with down syndrome: a randomized trial. Physical
Therapy. 2008; 88(1):114-122.
Level of Evidence (Oxford scale): 2b
Purpose: To test the effects of individualized, progressively more intense treadmill training on
developmental outcomes in infants with Down syndrome.
Methods: This was a randomized controlled trial, in which infants were randomly assigned to the higherintensity, individualized training group or the lower-intensity, generalized training group.
•
Participants
o 30 infants with Down syndrome.
o Eligibility criteria included: presence of a seizure disorder, non-correctable vision problems,
and any other medical conditions that would severely limit a child’s participation in the
treadmill intervention.
o A criterion for starting the treadmill intervention was the ability to take a minimum of 6
supported steps in a given minute on the treadmill. Most of the infants began the
intervention at 10 months of age.
•
(HG) Higher-Intensity, Individualized Training Group (n = 16)
o Training protocol included 8 minutes per day, 5 days per week, at a belt speed of 0.15m/s.
o As infants progressed, ankle belts were added, belt speed was increased, and daily
duration was increased in an effort to maximize the stepping response. These conditions
were initiated once the infants displayed the ability to take 10 steps per minute and
increased when they were able to take 20, 30, and 40 steps per minute.
30
•
(LG) Lower-Intensity, Generalized Training Group (n=14)
o Training protocol included 8 minutes per day, 5 days per week, at a belt speed of 0.15m/s.
•
Outcome Measures
o Motor performance was assessed with the Bayley Scales of Infant Development.
o Items monitored during each biweekly follow-up session included: moves forward using
pre-walking methods, raises self to standing position, walks sideways,/cruises, walks with
help, stands alone, walks alone and walks alone with good coordination.
o Parent-reported milestone achievement was also verified at each biweekly visit.
Results: Analysis of variance of the change in the numbers of alternating steps taken from study entry to
onset of independent walking revealed significant time (p<.0001) and interaction (p<.05) effects for the HI
group. Only moves forward using pre-walking methods and raises self to standing position reached
statistical significance (p=.01 and p=.05, respectively). There were no significant differences between the
HI and LG groups for the other milestones. Statistical power was low for each of these statistical tests and
was influenced by the loss of 6 infants during the study.
•
Infants in the LG group walked independently, on average, at 21.3 months.
•
Infants in the HI group walked independently, on average, at 19.2 months.
Critique & Conclusion: One of the most significant weaknesses of this study was the lack of blinding
to subjects, therapists and assessors, which could have led to biases in he intervention results. Another
weakness was insufficient follow-up for analysis, due to 6 infants being lost during the intervention. A
strength of this study was the ability of parents to be personally involved in implementing their child’s
intervention and assisting them to potentially walk earlier than they typically might. In conclusion,
regularly scheduled physical therapy can be supplemented with treadmill training, including high
intensity, individualized training, to facilitate a significantly earlier onset of independent walking
31
Discussion
After reviewing the selected research articles testing progressive resistance training, strength
training, agility training and treadmill training, it was found that such interventions have beneficial effects on
individuals of all ages with Down syndrome (Table 2). In infants, Ulrich found that regularly scheduled
physical therapy could be supplemented with treadmill training implemented by parents in the homes to
facilitate a significantly earlier onset of independent walking9,10. A treadmill walking program, three times
per week for 25 consecutive weeks, was also found to significantly improve muscle strength and balance in
aged adults2. In regards to strengthening programs, one study found that a 12-week program with a
combination of strengthening and cardiovascular exercise had a significant effect on upper and lower body
strength, as well as cardiovascular fitness in adults with DS6. In addition, 10-week progressive resistance
training programs were found to improve upper-limb muscle endurance and strength in adolescents7 and
lower-limb muscle strength in adults8 with DS. A 6-week progressive resistance exercise program was also
shown to improve lower-limb strength and overall balance in children with DS3. Finally, a study conducted
by Lin and Wuang (2012) found that lower extremity muscle strength and agility performance in
adolescents with DS improved significantly after a 6-week exercise program with a combination of treadmill
and virtual reality game protocols4.
These findings are significant because individuals of all ages with Down syndrome often
experience decreased upper and lower limb muscle strength. Among motor impairments demonstrated by
individuals with Down syndrome, muscle strength is one of the essential abilities in order to achieve
effective and functional movements4. These improvements can facilitate an earlier onset of walking,
allowing for greater independence with functional mobility, as well as interaction with the environment and
play. Improvement in strength has also been associated with positive changes in functional activities in
adults with Down syndrome2 and in work-related skills in people with intellectual disability12.
32
Conclusion
The results of the research studies provided an answer for my posed clinical question. It was found
that various strengthening interventions, such as progressive resistance training, treadmill training, and
agility training, have the potential to lead to improved level of independence in individuals with Down
syndrome. With improved strength, these individuals are better able to perform activities of daily living and
carry out their social and vocational roles, leading to decreased dependency on others, and in turn,
potentially improving their overall quality of life.
If I had the opportunity to work with my case study patient for a longer duration and outside of an
acute care setting, I would include treadmill training as a part of my interventions and plan of care. At my
next pediatric rotation and in the future as a physical therapist, I will be incorporating these types of
interventions for my patients. They are feasible, relatively inexpensive, safe, and most importantly have
evidence to show that they can improve the strength for individuals with Down syndrome.
33
References
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2. Carmeli E, Kessel S, Coleman R, Ayalon M. Effects of a treadmill walking program on muscle strength
and balance in elderly people with Down syndrome. Journal of Gerontology: MEDICAL SCIENCES.
2002; 57A(2): M106-M110.
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34
9. Ulrich DA, Lloyd MC, Tiernan CW, Looper JE, Angulo-Barroso RM. Effects of intensity of treadmill
training on developmental outcomes and stepping in infants with down syndrome: a randomized trial.
Physical Therapy. 2008; 88(1):114-122.
10. Ulrich DA, Ulrich BD, Angulo-Kinzler RM, Yun J. Treadmill training of infants with Down syndrome:
evidence-based developmental outcomes. Pediatrics. 2001;108(5). DOI:10.1542/peds.108.5.e84.
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February 10, 2013.
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35