NewGait: A Low-Cost Rehabilitation System to Improve Post-Stroke Gait (Biomechanical Adaptations)
Phase: NA
Conditions: Stroke
Sponsor: University of Michigan

NewGait: A Low-Cost Rehabilitation System to Improve 
Post-Stroke Gait (Biomechanical Adaptations) 
 
NCT06269367 
 
Date of IRB Approval: February 5, 2024 

1 
 
Background 
1 
Post-stroke gait recovery is a significant rehabilitation challenge. Stroke is the leading cause 
2 
of long-term adult disability worldwide.1 By 2030, nearly 4% of the US population is expected to 
3 
have had a stroke, leading to an estimated cost burden of ~$184B.2 Even after completion of 
4 
therapy, up to 80% of stroke survivors 
5 
experience significant gait impairment.3-5 
6 
Several gait therapies (e.g., treadmill training, 
7 
split-belt training, robotic training) have been 
8 
established;6-18 however, recovery after these 
9 
interventions is modest at best, and results 
10 
vary from significant to minimal 
11 
improvement.19 Therefore, there is a critical 
12 
need for rigorous science-based approaches 
13 
to effectively address post-stroke gait deficits. 
14 
Current comparable solutions are limited to a single joint, expensive, and/or ineffective: 
15 
Consumers can choose a variety of devices for post-stroke gait training, but many barriers to 
16 
adoption exist, especially for those that are economically disadvantaged. While there is a wide 
17 
range of gait devices, from ankle foot orthoses (AFOs) to powered exoskeletons, the focus of our 
18 
comparison will be on other lightweight and “low-cost” devices (Fig. 1). Regular AFOs, though 
19 
simple and cost-effective, may lead to disuse atrophy20,21 and reduce gait efficiency by 
20 
decreasing Achilles tendon excursion and propulsive forces during walking.22,23 Further, they 
21 
only target the ankle joint, whereas the hip, knee, and trunk play an 
22 
important role in gait and balance. TheraTogs (Fig. 2a) and 
23 
TheraSuit (Fig. 2b) closely resemble our current technology 
24 
(NewGait). However, these devices primarily target the pediatric 
25 
market (although adult versions exist) and evidence for these 
26 
devices is of low quality.24 Both devices fit like close-fitting 
27 
clothing, which increases donning and doffing time. They are also 
28 
3-5x more expensive than typical Medicare reimbursement rates for 
29 
conventional AFOs,25 which reduces the likelihood of insurance 
30 
coverage and affordability. ReWalk ReStore is a powered, soft 
31 
robotic exosuit for ankle plantarflexion and dorsiflexion assistance24 (Fig. 2c). Though effective 
32 
in improving gait speed, it is a relatively large and expensive device (~$30K) and only assists the 
33 
ankle joint.  Thus, there is a significant unmet need for an effective, affordable, and portable, gait 
34 
mobility/rehabilitation device for stroke survivors.  
35 
Prior research suggests that rehab interventions need to be intense,26,27 highly repetitive,27-29 and 
36 
task-oriented30 to induce neuroplasticity31,32 – a key element for long-lasting gait recovery. Yet, 
37 
an average stroke patient spends only ~20% of their physical therapy time on gait-oriented 
38 
activities.33 The dosage of therapy could be increased substantially if therapy can be transferred 
39 
outside the clinic; however, most therapeutic solutions are only assistive (thus, not intense) and 
40 
Fig. 2 Comparable devices. 
Fig. 1 Chart comparing NewGait to existing devices. 

2 
 
too costly for use in a patient’s home. Moreover, most low-cost commercial solutions are not 
1 
designed based on end-user feedback and biomechanical data, which limits usability and optimal 
2 
patient outcomes. Hence, many current approaches show clinically small and unsustainable 
3 
improvements in gait and mobility after the stroke.34,35 Given that repetitive and intensive 
4 
treatments that challenge the central nervous system are crucial for inducing neuroplasticity and 
5 
promoting gait recovery after stroke,35 a therapeutic solution that caters to user needs and is 
6 
widely adapted is needed to create a paradigm shift in post-stroke 
7 
rehabilitation.  
8 
Our solution. We will leverage the existing wearable, gait system 
9 
(NewGait) and refine it for post-stroke gait rehabilitation based on 
10 
end-user feedback and biomechanical modeling. The current device 
11 
(costs $520; Fig. 3) is highly preferred by clinicians and used in patient 
12 
populations suffering from a wide range of neurological conditions, 
13 
including stroke, multiple sclerosis, and Parkinson’s disease. Our 
14 
preliminary data show that NewGait induces biomechanical gait 
15 
adaptations and improves gait and balance in stroke survivors. 
16 
However, feedback from clinicians has indicated the need for design 
17 
improvements. Further, it is currently unknown how our device performs against our immediate 
18 
competitors (such as TheraTogs, TheraSuit, TripleFlex, or other similar devices). Hence, in this 
19 
STTR Phase-I, we propose to perform biomechanical experiments, and compare the short-term 
20 
adaptations and usability with other comparable devices. Successful completion of this project 
21 
will provide much-needed data for improving customer experience, boosting sales, acquiring 
22 
new markets, and more.  
23 
 
24 
Study Aims 
25 
Significance. Restoration of gait function is a major goal in post-stroke rehabilitation, yet most 
26 
stroke survivors experience significant gait deficits when discharged from physical therapy. 
27 
Current evidence suggests that intense, highly repetitive, and task-oriented rehabilitation 
28 
interventions are essential to promote optimal neuroplasticity—a critical factor for long-lasting 
29 
gait recovery. Accordingly, several therapeutic solutions involving specialized treadmills, robotic 
30 
devices, and exosuits have been designed to induce neuroplasticity and post-stroke gait recovery. 
31 
However, these gait training devices are typically expensive and bulky, making them less 
32 
accessible to most clinics and patients. As a result, stroke survivors do not receive adequate dosage 
33 
of gait therapy to achieve meaningful clinical improvements, creating a significant clinical need 
34 
for new and efficient strategies to increase therapy dosage. While some lightweight and “low-cost” 
35 
commercial devices exist (e.g., TheraSuit, TheraTogs, TripleFlex, or other similar devices), they 
36 
are not often designed based on multi-user feedback and robust biomechanical data and their 
37 
clinical utility have not been tested in stroke survivors, thereby limiting usability and effectiveness. 
38 
All these limitations create barriers to access for effective gait training, particularly for 
39 
economically disadvantaged and rural populations. Thus, there is a significant unmet need for an 
40 
Fig. 3 The NewGait system 

3 
 
effective, affordable, and portable gait mobility/rehabilitation device that permits evidence-based 
1 
gait training accessible to most stroke survivors. 
2 
Innovation. We will develop an optimized wearable system based on an innovative human-
3 
centered design approach (design sprints and think aloud technique) and biomechanical 
4 
simulations and test its clinical utility for post-stroke rehabilitation. The device is non-powered, 
5 
lightweight, low-cost, and built to be more accessible to the general stroke population. Our 
6 
modular design will promote adoption by allowing users to change configurations based on patient 
7 
needs.  
8 
Phase I Goals. Our interdisciplinary team will (1) identify the optimal biomechanical design with 
9 
improved usability based on end-user feedback and musculoskeletal modeling, (2) refine the 
10 
current NewGait prototype to meet stroke-specific needs, and (3) perform a comparative clinical 
11 
feasibility study to establish the clinical potential of the NewGait device in comparison with other 
12 
comparable devices.  
13 
Aim 1: Identify an optimal NewGait design based on end-user feedback and musculoskeletal 
14 
modeling. Aim 1a. We will obtain end-user preferences and requirements through a series of 
15 
human-centered design sprints with stroke survivors and their caregivers, and physical therapists, 
16 
to inform potential design changes. Aim 1b. We will simulate subject-specific NewGait training 
17 
for walking using a rigorously vetted musculoskeletal modeling software (OpenSim) to identify 
18 
the effect of various design configurations on post-stroke gait mechanics. We will also investigate 
19 
the effects of pertinent geometric and material parameters on lower-extremity joint moments and 
20 
powers using inverse dynamics. Muscle activation effects will be quantified using computed 
21 
muscle control. Milestones: 1) Determine end-user preferences and requirements for a stroke-
22 
specific NewGait design; and 2) using musculoskeletal modeling, produce a look-up table to 
23 
provide changes in joint moments, powers, and muscle activations as a function of length, stiffness, 
24 
and attachment points of the elastic bands.  
25 
Aim 2: Refine the current prototype and perform benchtop testing to validate durability. We 
26 
will refine the current NewGait prototype to meet stroke-specific needs and validate its mechanical 
27 
behavior during repeated cyclical loading via extensive benchtop testing of the interfaces between 
28 
the straps, anchor points, and elastic bands. We will also perform fatigue analysis to evaluate 
29 
durability. Milestones: Produce a light-weight, durable prototype that satisfies end-user 
30 
preferences and modeling results. 
31 
Aim 3: Examine short-term gait adaptations and clinical feasibility in stroke survivors. We 
32 
will conduct a pilot randomized, crossover study comparing NewGait with comparable devices 
33 
based on short-term biomechanical adaptations, clinical feasibility, and adoption potential for day-
34 
to-day activities in chronic stroke survivors. Outcomes will be evaluated at three levels: 1) 
35 
biomechanical (gait mechanics); 2) neurophysiological (muscle activation, and coordination); and 
36 
3) clinical (walking speed), which will help establish the mechanistic underpinnings of training-
37 
related adaptations. We will gather end-users’ feedback on the usability, comfort, and satisfaction 
38 
between devices. Milestones: Obtain and compare (a) gait mechanics, muscle activation, and gait 
39 

4 
 
speed data between NewGait and competitors’ devices, and (b) participant feedback on usability, 
1 
comfort, and satisfaction for the NewGait and competitive devices. 
2 
Phase-I Impact. This Phase-I STTR project will improve the current device based on end-user 
3 
feedback and musculoskeletal modeling and demonstrate the clinical potential of NewGait for 
4 
restoring gait function in stroke survivors against its comparable, competitive devices. The results 
5 
will also provide insights into the mechanistic basis for gait adaptations following NewGait 
6 
training. The resulting data will support an STTR phase II grant, where the long-term effects of 
7 
the NewGait will be assessed in a large-scale randomized control trial. 
8 
 
9 
Note that Aim 1a is exempt project and we have a separate exempt 3 IRB approval 
10 
(HUM00221923). Aim 2 is not a human subjects study. Aim 3 is a clinical trial based on 
11 
NIH definition of a clinical trial.  All devices that are used in the training are considered to 
12 
be class 1 510(K) exempt devices.  
13 
 
14 
This study will not meet the Food and Drug Administration Amendments Act (FDAAA) of 
15 
2007 (FDAAA 801) definition of an “applicable clinical trial” as the studied devices are not 
16 
subject to section 510(k), 515, or 520(m) of the FDC act.  
17 
 
18 
We note that the devices used in this study will fall into a generic category of Class I 510(k) 
19 
exempt devices as defined by 21 CFR Parts 862-892 and would not require FDA review. These 
20 
devices would come under one of the following categories: (1) Limb Orthosis (regulation no. 
21 
890.3405) and (2) Truncal Orthosis (regulation no. 890.3490), (3) Nonmeasuring exercise 
22 
equipment (regulation no. 890.5370), (4) Daily Activity Assist Device (regulation no. 890.5050). 
23 
Many of the commercial robotic devices (Lokomat, Armeopower, Armeospring, etc.) that are 
24 
powered and actuated using motors are also 510(k) exempt under regulation no. 890.1925 
25 
(Isokinetic testing and evaluation system). 
26 
Methods 
27 
The acute effects of NewGait training will be studied using 
28 
a pre-post randomized crossover study design in 
29 
individuals with chronic stroke (Fig. 4). Participants will 
30 
serve as their own control and undergo training with 
31 
NewGait, and other comparable control devices on the 
32 
same or different days. The training session order will be 
33 
randomized. Outcomes will be evaluated at three levels: 1) 
34 
biomechanical (gait mechanics); 2) neurophysiological 
35 
(changes in EMG activity and muscle coordination using 
36 
synergy analysis); 3) clinical (changes in gait speed). Our 
37 
primary outcomes are changes in a) gait speed and b) ankle muscle activation. Our secondary 
38 
outcome measure is changes in paretic leg propulsive force. Our other outcome measures are 
39 
Fig. 4 A schematic of the testing protocol. GRF 
= ground reaction forces 

5 
 
muscle coordination, other lower extremity muscle activation, and paretic leg loading. Finally, we 
1 
will conduct brief in-person interviews at the end of each session to collect feedback on usability, 
2 
comfort, satisfaction, and the potential for adoption of the device in their day-to-day activities.  
3 
Subjects and Recruitment: We anticipate that about 18 subjects will be needed to meet the 
4 
primary endpoint. We will recruit 30 participants who are diagnosed with stroke to participate in 
5 
this study to account for screening failure and drop-outs. Subjects will be recruited via face-to-
6 
face contact, email, public advertisements, posting on UMClinicalStudies.org website/social 
7 
media, or through a stroke registry (IRB: HUM00099109). Additionally, subjects may be 
8 
recruited from subject pools created through existing IRBs (HUM00073356, and 
9 
HUM00087962). Subjects may be pre-screened to ensure their eligibility before coming to the 
10 
lab. 
11 
Inclusion Criteria 
12 
1. Aged between 40 to 75 years 
13 
2. Unilateral cortical or subcortical stroke 
14 
3. Chronic stroke (≥ 6 months) At least 6 months following their stroke 
15 
4. Able to walk independently with/without assistive devices for 5-10 mins (~150m) 
16 
5. No significant cognitive deficits as determined by the Mini Mental State Examination 
17 
(MMSE) score (score ≥ 22) 
18 
Exclusion Criteria 
19 
A subject is not eligible for inclusion if any of the following criteria apply: 
20 
1. Cerebellar stroke 
21 
2. Traumatic brain injury 
22 
3. History of unstable heart condition, uncontrolled diabetes or hypertension 
23 
4. History of a recent lower-extremity trauma or fracture 
24 
5. History of significant orthopedic or neurological conditions that could limit walking ability 
25 
(e.g., multiple sclerosis, total knee replacement) 
26 
6. History of significant spatial neglect 
27 
7. Joint contractures or significant spasticity in the lower-extremity 
28 
8. History of a recent Botulinum Toxin (Botox) injection to the lower-extremity muscles (≤ 
29 
3 months) 
30 
9. Pregnant or actively planning to become pregnant (self-reported) 
31 
10. Inability to communicate or unable to consent 
32 

6 
 
We do not plan to exclude subjects based on stroke severity/impairment or stroke location as a 
1 
post-hoc analysis would inform us on appropriate patient population selection for future 
2 
interventional studies. We note that the risks of participating in the study do not change based on 
3 
the severity or location of the stroke,36,37 There are no imaging requirements for the study 
4 
subjects and interpretation (performed using chart reviews, medical records, or by the stroke 
5 
physician) of the images (if available through medical records) will be used only to characterize 
6 
the lesion location, severity, and type of injury for publication purposes.  
7 
Experimental Procedures  
8 
The experiment may consist of about 4 successful sessions/visits depending on subject’s 
9 
availability. Each session will last approximately 2-3 hours in duration. Participants may be 
10 
required to undergo additional visits in the event of inability to complete a session for any reason 
11 
(e.g., technical difficulty, equipment issues). Different conditions may happen on the same day 
12 
or different, depending on the participant’s ability and availability.  
13 
Screening, Orientation, and Informed Consent Visit: Subject will meet an authorized research 
14 
personnel in the Neuromuscular and Rehabilitation Robotics Laboratory (NeuRRo Lab). During 
15 
this visit, the participant will be provided with detailed information about the study, the risks and 
16 
benefits of participation, and the nature of study procedures, including orientation to various 
17 
testing devices used in this study. A study member will screen the subjects for the eligibility 
18 
criteria using screening questionnaires and health related assessments including chart reviews. 
19 
The screening process may be completed prior to coming to the lab through online questionnaire 
20 
(e.g., RedCap) or phone calls. During the screening/orientation session, we will also orient the 
21 
participant to the study procedures. We may also measure their muscle strength of various joints 
22 
by having them perform maximal contractions against manual resistance or instrumented 
23 
dynamometers. We may also have them walk on a treadmill to test their ability to walk and to 
24 
perform a biomechanical evaluation. We may also measure their movement ability using 
25 
standardized test procedures. These tests include 10-meter walk test, 6-minute walk test, clinical 
26 
assessments like Fugl-Meyer evaluation, and balance assessments.  
27 
Experimental Paradigm 
28 
Once screening has been completed, we will begin recording baseline measurements of the 
29 
subject’s biomechanics and physiology.  
30 
Beginning of the Session 
31 
Using the methods and equipment noted above, we will measure the subject’s spatiotemporal 
32 
gait parameters. We will apply surface electromyography (EMG) sensors to many of the key 
33 
muscles used in gait [e.g., vastus medialis (VM), rectus femoris (RF), medial hamstring (MH), 
34 
lateral hamstring (LH), tibialis anterior (TA), medial gastrocnemius (MG), soleus (SO), and 
35 
gluteus medius (GM)]. Typically, electrodes will be secured to the skin using self-adhesive tapes 
36 
and cohesive flexible bandages. Electrode placement will be carried out according to the 
37 

7 
 
guidelines established by the international SENIAM initiative (www.seniam.org). Should 
1 
electrode positions be occluded by the device, electrodes will be placed over non-occluded but 
2 
similar synergist muscles. The quality of the EMG signals will be visually inspected to ensure 
3 
that the electrodes were appropriately placed. We will then apply reflective markers that can 
4 
track their movements during walking. 
5 
Treadmill Walking 
6 
First, subjects will walk for about 10 meters overground so walking speed can be determined. 
7 
Then, they will walk for a few minutes on the treadmill so that we can measure their normal 
8 
biomechanics with or without feedback. A body-weight supporting harness may be used as an 
9 
additional support in case the participant has substantial motor impairments or feels unsecure 
10 
without the provision of supporting harness. Next, intervention or control device will be put on 
11 
the participants based on a random selection. Because the mobility device is passive (i.e., does 
12 
not add energy to the subject’s movement, as a motor would) it is of minimal risk to the subject. 
13 
Afterwards, another approximately 10 meter overground walk will be performed to determine 
14 
walking speed. Then, about 5 trials will be recorded during which the participant will walk on 
15 
the treadmill for a few minutes while biomechanics (e.g., kinematics and kinetics) and EMG 
16 
activity and spatiotemporal gait parameters are being recorded. We may also provide feedback of 
17 
their muscle activation or biomechanics (e.g., kinematics, kinetics) during the trials to improve 
18 
their engagement during the experiment. Afterwards, the device will be taken off and another 
19 
approximately 3-minute walk on the treadmill will be recorded for post training measurements. 
20 
At the end, the participant will walk overground for about 10-meters to determine gait speed. 
21 
End of the Session 
22 
After completion of data collection, participants will provide end-user feedback regarding the 
23 
device. Subjects will be tested for their subsequent condition (e.g., control condition) or asked to 
24 
return to the lab for the subsequent sessions.  
25 
Paradigms and Assessments 
26 
The following tools may be used to quantify the biomechanical and neurophysiological effects of 
27 
walking with assistive devices. All assessment tools are noninvasive and are of minimal risk to 
28 
the subject and have been previously approved by the IRB. 
29 
1. Muscle Activation and Coordination: The magnitude of muscle activation and co-
30 
contraction of the antagonist muscles during testing will be measured using 
31 
Electromyography (EMG) by means of noninvasive surface electrodes. Brands used in 
32 
our lab include: (Trigno Wireless EMG, Delsys, Inc., Natick, MA, USA) and (Model 
33 
MA-311, Motion Labs Systems, Inc., Baton Rouge, LA, USA). Previously accepted for 
34 
use on human subjects in IRBs (HUM00081480, HUM00073356, HUM00130845, 
35 
HUM00087962, and HUM00080244). 
36 

8 
 
2. Kinematics and Kinetics: The subject's movement patterns, ground reaction forces, and 
1 
joint moments during the experiment will be evaluated using instrumented treadmill and 
2 
motion capture camera system or similar instruments (i.e., angle encoders or 
3 
goniometers) and monitored over time to see how the subject walks with and without 
4 
assistive devices. We will compare the subjects gait kinematics and kinetics for various 
5 
assistive devices. Previously accepted for use on human subjects in IRB (HUM00073356, 
6 
HUM00087962, and HUM00133860). 
7 
3. Spatiotemporal Gait Parameters: Mobility lab (APDM Inc.) – which measures temporal-
8 
spatial events and limb accelerations, or instrumented walkway/treadmill will be used to 
9 
measure the subject’s spatiotemporal gait parameters (e.g., gait speed, cadence, stride 
10 
length, stride duration, etc.) before, during, and after assisted walking. Previously 
11 
accepted for use on human subjects in IRB (HUM00087962). 
12 
Data Analyses 
13 
Gait Mechanics Testing. Ground reaction forces (GRFs) during walking will be collected on both 
14 
legs using an instrumented treadmill. Surface EMG signals from the lower-extremity muscles will 
15 
also be collected according to SENIAM guidelines. All evaluations will be performed at their self-
16 
selected walking speed.38 Speed may be adjusted if the participant has difficulty in walking at their 
17 
seif-selected speed. All biomechanical data (including EMG) will be time normalized to stance 
18 
and swing phase of the gait cycle.39-40 We will examine the changes (from baseline) in vertical and 
19 
antero-posterior propulsive forces recorded during walking (with paretic-leg propulsive forces 
20 
being the primary focus) and compared across conditions. Where feasible, we may also collect 
21 
kinematic (e.g., joint angles) and kinetic (e.g., joint moment and power) data to evaluate training 
22 
effects during walking.  
23 
Muscle Activation and Coordination during Gait. The mean EMG activity during walking will 
24 
be evaluated to quantify the changes in lower-extremity muscle excitation due to the training. 
25 
Apart from the amplitude-related EMG evaluation, muscle coordination will be studied using 
26 
nonnegative matrix factorization (NMF)41 as we have done previously.42-44 Lower-extremity 
27 
EMG data will be collected using standard protocols.16,43,44 The raw EMG data will be band-pass 
28 
filtered (20-500 Hz), rectified, and smoothed with a zero-phase low-pass Butterworth filter (2nd 
29 
order, 6 Hz).43,44 EMG data for each stride will be time/amplitude normalized and concatenated 
30 
together. The similarity between the synergies will be computed by calculating the angle 
31 
between the synergies and the independence of neural control signals (i.e., the ability to 
32 
selectively activate muscles during gait) will be characterized by studying the number of muscle 
33 
modes required to account for muscle activation during walking. 
34 
Clinical Measure: The 10-Meter Walk Test (10-MWT) will be performed using standardized 
35 
clinical assessment procedures to evaluate changes in walking speed with training.45,46 The 
36 
individual will be instructed to walk at their self-selected pace on a 12-meter straight walkway, 
37 

9 
 
while a stopwatch will be used to time the intermediate 10-meter walk (participants will be given 
1 
one meter to accelerate and decelerate).  
2 
End-User Evaluation of Devices: End-user insights are extremely critical when designing novel 
3 
rehab devices 47,48 however, there is very limited literature addressing common usability concerns 
4 
for gait re/training or exoskeleton devices.49 In this study, in addition to the assessment of gait 
5 
mechanics, muscle activation, and walking speed, we will complement the clinical measures by 
6 
assessing usability factors for each device, such as ease of use, comfort, satisfaction, perceived 
7 
effectiveness, and potential for adoption in day-to-day activities. To collect these data, first we will 
8 
observe the patient interacting with the device during the session and record time needed to 
9 
don/doff the device, ability to follow instructions to use the device, questions they asked about the 
10 
device or its use, any difficulties using the device, and device malfunctions. Following the 
11 
treadmill walking with the device, we will interview the stroke survivor and caregiver about their 
12 
experience with the device using a semi-structured interview format and Likert-scales. To design 
13 
the interview guide and Likert scales, we will build on what we learn from design sprints and think 
14 
aloud sessions during prototyping to ensure that we evaluate factors that end-users find most 
15 
relevant for uptake and adoption of gait devices. 
16 
 
17 
Statistical Analyses 
18 
Outcomes will be evaluated at three levels: 1) biomechanical (gait mechanics); 2) 
19 
neurophysiological (changes in EMG activity and muscle coordination using synergy analysis); 
20 
3) clinical (changes in gait speed). Our primary outcomes are changes in a) gait speed and b) 
21 
ankle muscle activation. Our secondary outcome measure is changes in paretic leg propulsive 
22 
force. Our other outcome measures are muscle coordination, other lower extremity muscle 
23 
activation, and paretic leg loading. Finally, we will conduct brief in-person interviews at the end 
24 
of each session to collect feedback on usability, comfort, satisfaction, and the potential for 
25 
adoption of the device in their day-to-day activities. 
26 
Linear mixed models (or other similar analysis) will be used to compare the primary, secondary, 
27 
and other outcomes between NewGait and control/comparative devices/conditions. Participant’s 
28 
demographics (e.g., sex) may be used as a covariate. Exploratory linear regression analysis may 
29 
be used to determine the association between changes in biomechanical and neurophysiological 
30 
variables and changes in gait speed. For data collected on the end-user experience of each 
31 
device, we will use complementary methods of analyzing qualitative and quantitative data.  
32 
This is a pilot study; hence, sample size is based on feasibility considerations. Using a two-sided 
33 
test with a conservatively corrected α of 0.0167, 18 subjects will provide >80% power to detect 
34 
significant differences with an effect size of ‘f’ of 0.40 (partial η2= 0.14) (GPower3.1). 
35 
Safety Considerations 
36 

10 
 
The study procedures for this experiment are considered to be no greater than minimal risk. All 
1 
procedures are noninvasive, the resistance methods are passive, and there are no children or 
2 
vulnerable groups involved in this study. Almost all of the experimental testing procedures have 
3 
been approved previously for use on human subjects (as a minimal risk procedure) in our other 
4 
IRBs (HUM00133860, HUM00081480, HUM00073356, HUM00080244, HUM00130845, and 
5 
HUM00087962). The potential risks for this study are described below: 
6 
Potential Risks 
7 
Surface EMG Related: 
8 
• Allergic Reaction (infrequent): Subjects may experience allergic reactions from the 
9 
application of electrode paste and adhesive tapes necessary for surface EMG recordings. 
10 
We will use hypoallergenic tapes to minimize allergic reactions. If redness or excessive 
11 
itching occurs, the area will be monitored closely by study staff and testing will be ended 
12 
at their discretion or in accordance with the subject’s wishes.  
13 
Walking Related: 
14 
• Spasms (Infrequent): If subjects suffer from spasticity, the initial movement while 
15 
walking with resistance may trigger muscle spasms. This will gradually settle down with 
16 
time. The resistance will be adjusted if this occurs to ease the spasms. 
17 
• Skin irritation (Infrequent): Subjects may experience some skin irritation from the cuffs 
18 
due to bracing attached to the limbs. If subjects experience irritation, adequate padding 
19 
(coban or foam pads) will be provided between their skin and the cuffs to reduce the 
20 
amount of irritation. 
21 
• Tripping/Fall (Infrequent): Subjects may trip if walking with resistance/assistance, 
22 
especially if the subject has weak muscles. To minimize risk, subjects will be able to hold 
23 
handrails, which increases stability while walking. We will also provide them with an 
24 
option of wearing a body weight supporting harness to improve the feeling of safety 
25 
during some activities. However, in our experience many people do not prefer wearing a 
26 
harness, as the harness may produce some amount of discomfort while walking (a feeling 
27 
of tight compression). Subjects may also experience tripping or falling during functional 
28 
evaluation. However, these risks are no more than what they would encounter in their 
29 
day-to-day activities. For safety purposes, the subject will always be under close 
30 
supervision of a researcher while undergoing functional evaluation. 
31 
• Muscle or joint pain (Infrequent): During or following the experiment, subjects may feel 
32 
temporary or persistent muscle aching or joint pain, or general fatigue. Any discomfort 
33 
may be improved by adjusting the resistance, providing appropriate rest breaks at any 
34 
time during the experiment, or using over-the-counter pain reliever. 
35 

11 
 
• Risk of fatigue (Likely): There is a risk that subjects can become fatigued from walking 
1 
with resistance for prolonged periods of time. Subjects will be allowed to rest and can 
2 
also choose to end the test at their own will at any time. As with any research study, there 
3 
may be additional risks that are unknown or unexpected. As described above, these risks 
4 
will be minimized by allowing subjects to rest as needed and withdraw from the study 
5 
voluntarily at any time. A research assistant will stand near subjects during the tests and 
6 
will actively observe the subject for any distress. All devices will be built to eliminate 
7 
risks of irritation or severe discomfort.  
8 
• Muscle Fatigue or Soreness (Infrequent): During measurement of muscle strength, 
9 
subjects may experience temporary muscle fatigue and soreness. Although this soreness 
10 
may persist for a period of several days following testing, this level of soreness is not 
11 
greater than they would experience following a regular exercise session.  
12 
• Loss of privacy (Rare): A loss of privacy may occur from participating in this study. The 
13 
seriousness of a breach of this information is minimal. All data and medical information 
14 
collected from participants will be considered privileged and held in confidence; 
15 
participants will be assigned confidential codes and no identifying personal data will be 
16 
stored with study data. RedCap™ (Research Data Capture) system may be utilized for the 
17 
storage of patient demographic information, clinical assessment scores, and all processed 
18 
data via encrypted university computers. The raw/unprocessed data will be coded with a 
19 
unique patient identifier and stored offline on a password protected laboratory computer. 
20 
• Unforeseeable Risks (Rare): As with any research study, there may be additional risks 
21 
that are unknown or unexpected. 
22 
 
 
23 

12 
 
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