Gait, Frontal, Healthy
Conditions
Brief summary
The investigators are examining how weight distribution affects the way people walk, in terms of joint kinematics, kinetics, and muscle activity. The investigators are measuring these quantities while people walk while wearing a weighted belt. The investigators distribute the weights and walk for specified periods. They hypothesize that greater weight will have a greater effect on walking.
Detailed description
The purpose of this study is to examine how the amount and distribution of weight on the pelvis affects how people walk. The investigators two factors, weight and placement. They are examining how these factors affect muscle activation, joint motions and foot forces. The investigators plan to recruit 40 healthy adult individuals. Each of the 20 experimental conditions (3x3 factorial and one control condition with no weight) will be recorded immediately in a single session. The investigators hypothesize that weight amount, gait speed and weight distribution will all affect how people walk, which will lead towards optimized design of hip exoskeletons.
Interventions
OTHERWeight belt
Wearing belt around waist with various weights attached.
Sponsors
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
University of Texas at Austin
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Willing to commit to the full experimental session
Exclusion criteria
* Functionally relevant lower limb musculoskeletal injury * Functionally relevant osteoarthritis and weight bearing restrictions * Severe respiratory problems that restrict the wearer from using a metabolic rate apparatus * Patients with cardiac issues may be included, but the cardiac issue will be noted in the health history questionnaire
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pelvic Obliquity | One day | Amount of pelvic obliquity in response to weighted belt measured using optical motion capture |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Knee Flexion Angle During Swing Phase | One Day | Knee flexion angle range of motion measured using optical motion capture |
| Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | One day | EMG signals were normalized via the mean-dynamic method (Burden and Bartlett, 1999), centering the EMG signal around 1. For data analysis, the EMG signal was integrated along each gait phase to calculate the integrated EMG (iEMG) values. For the gastrocnemius, we extrated the iEMG during the pre-swing phase only. The iEMG was normalized to average during walking, resulting in arbitrary units. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Weight and Placement Changing where weight is distributed on belt around pelvis, specifically, bilaterally, 4th lumbar area, unilaterally on the left side. Also changing weight amounts at 4, 6 and 8 kg.
Weight belt: Wearing belt around waist with various weights attached. | 21 |
| Total | 21 |
Baseline characteristics
| Characteristic | Weight and Placement |
|---|---|
| Age, Continuous | 26.7 Years STANDARD_DEVIATION 5.75 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 20 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants |
| height | 172 cm STANDARD_DEVIATION 7.58 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants |
| Race (NIH/OMB) Asian | 5 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants |
| Race (NIH/OMB) More than one race | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) White | 15 Participants |
| Region of Enrollment United States | 21 participants |
| Sex: Female, Male Female | 9 Participants |
| Sex: Female, Male Male | 12 Participants |
| weight | 65.9 kg STANDARD_DEVIATION 8.53 |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 21 |
| other Total, other adverse events | 0 / 21 |
| serious Total, serious adverse events | 0 / 21 |
Outcome results
Primary
Pelvic Obliquity
Amount of pelvic obliquity in response to weighted belt measured using optical motion capture
Time frame: One day
Population: Healthy individuals
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Weight and Placement | Pelvic Obliquity | No weight | -0.55 degrees | Standard Deviation 2.79 |
| Weight and Placement | Pelvic Obliquity | 4 kg and bilateral placement | -0.83 degrees | Standard Deviation 2.89 |
| Weight and Placement | Pelvic Obliquity | 6kg and unilateral weight distribution | -1.2 degrees | Standard Deviation 3.05 |
| Weight and Placement | Pelvic Obliquity | 8kg and unilateral weight distribution | -0.7 degrees | Standard Deviation 2.97 |
| Weight and Placement | Pelvic Obliquity | 4 kg and lumbar placement | -0.19 degrees | Standard Deviation 2.91 |
| Weight and Placement | Pelvic Obliquity | 6 kg and lumbar placement | 0.08 degrees | Standard Deviation 2.93 |
| Weight and Placement | Pelvic Obliquity | 8kg and lumbar weight distribution | 0.45 degrees | Standard Deviation 2.94 |
| Weight and Placement | Pelvic Obliquity | 4kg and unilateral | -0.76 degrees | Standard Deviation 2.98 |
| Weight and Placement | Pelvic Obliquity | 6kg and unilateral | -0.8 degrees | Standard Deviation 2.83 |
| Weight and Placement | Pelvic Obliquity | 8kg and unilateral | -1.15 degrees | Standard Deviation 2.77 |
p-value: 0.05ANOVA
Secondary
Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking
EMG signals were normalized via the mean-dynamic method (Burden and Bartlett, 1999), centering the EMG signal around 1. For data analysis, the EMG signal was integrated along each gait phase to calculate the integrated EMG (iEMG) values. For the gastrocnemius, we extrated the iEMG during the pre-swing phase only. The iEMG was normalized to average during walking, resulting in arbitrary units.
Time frame: One day
Population: Healthy Individuals
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | No weight | 1.16 arbitrary units | Standard Deviation 0.53 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 4 kg and bilateral | 1.14 arbitrary units | Standard Deviation 0.48 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 6kg and bilateral | 1.20 arbitrary units | Standard Deviation 0.55 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 8kg and bilateral | 1.23 arbitrary units | Standard Deviation 0.53 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 4kg and lumbar | 1.24 arbitrary units | Standard Deviation 0.66 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 6kg and lumbar | 1.20 arbitrary units | Standard Deviation 0.54 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 8kg and lumbar | 1.19 arbitrary units | Standard Deviation 0.56 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 4kg and unilateral | 1.19 arbitrary units | Standard Deviation 0.49 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 6kg and unilateral | 1.20 arbitrary units | Standard Deviation 0.51 |
| Weight and Placement | Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking | 8kg and unilateral | 1.10 arbitrary units | Standard Deviation 0.43 |
p-value: 0.05Mixed Models Analysis
Secondary
Knee Flexion Angle During Swing Phase
Knee flexion angle range of motion measured using optical motion capture
Time frame: One Day
Population: Healthy Individuals
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Weight and Placement | Knee Flexion Angle During Swing Phase | No weight | 68.8 degrees | Standard Deviation 8.5 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 4 kg with bilateral | 67.66 degrees | Standard Deviation 8.84 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 6 kg with bilateral | 68.03 degrees | Standard Deviation 7.49 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 8 kg with bilateral | 67.99 degrees | Standard Deviation 7.95 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 4 kg with lumbar | 66 degrees | Standard Deviation 6.2 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 6kg with lumbar | 66.13 degrees | Standard Deviation 7.01 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 8kg with lumbar | 67.4 degrees | Standard Deviation 9.84 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 4kg with unilateral | 68.41 degrees | Standard Deviation 8.09 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 6kg with unilateral | 68.02 degrees | Standard Deviation 8.57 |
| Weight and Placement | Knee Flexion Angle During Swing Phase | 8kg with unilateral | 66.23 degrees | Standard Deviation 6.72 |
p-value: 0.05Mixed Models Analysis