Locomotion Adaptation Deficits in Older Adults With Mild Cognitive Impairment and Alzheimers Disease
NCT Number: NCT06484244
Status: RECRUITING
Study Type: INTERVENTIONAL
Phases: NA
Conditions: Alzheimers Disease|Mild Cognitive Impairment
Interventions: OTHER: 5 Sessions of Split-belt treadmill-based locomotor adaptation|OTHER: Split-belt treadmill-based locomotor adaptation
Sponsor: Emory University
Collaborators: National Institute on Aging (NIA)
Sex: ALL
Age: ADULT, OLDER_ADULT
Enrollment: 60
Study Design: Allocation: NON_RANDOMIZED|Intervention Model: PARALLEL|Masking: NONE|Primary Purpose: TREATMENT
Start Date: 2024-07-02
Completion Date: 2025-06-01
Locations: Emory Rehabilitation Hospital, Atlanta, Georgia, 30322, United States

Summary:
In people with Mild Cognitive Impairment (MCI) and Alzheimer's Disease (AD), reduced capacity for locomotor adaptation is a fundamental but poorly understood mechanism that can be a sensitive biomarker of cognitive-motor impairments. It is also an important therapeutic target for exercise-based interventions to improve walking function. The overall goal of this study is to understand the effects of MCI and AD on locomotor adaptation and walking function.

Primary Outcome Measures: Change in Adaptation Magnitude Assessed as Peak Step Length Symmetry, Locomotor adaptation is the ability to adjust stepping movements to changing environmental demands via trial-and-error processing. Step length symmetry data from the split-belt phase will be used to evaluate each individual's locomotor adaptation magnitude capacity by assessing the peak step length symmetry in the early adaptation period., Baseline (Pre-training), Week 2 (Post-training)|Change in Adaptation Rate Assessed as the Number of Steps to Reach Step Symmetry, The adaptation rate is assessed as the number of steps required to reach a plateau in step symmetry during late adaptation., Baseline (Pre-training), Week 2 (Post-training)|Change in 10-Meter Overground Walk Test, Gait speed is assessed with the 10-Meter Overground Walk Test. The 10-Meter Overground Walk Test is used to assess walking speed over a short distance. A 10 meter (m) walkway over solid flooring will be measured and marked at start (0 m), 2 m, 8 m, and finish (10 m). Participants will be asked to complete three trials of the 10 m walk at their comfortable self-selected walking speed. The time for the three trials for each speed will be averaged and gait speed converted to meters/second., Baseline (Pre-training), Week 2 (Post-training)|Change in 6-Minute Walk Test, Gait endurance is assessed with the 6-minute walk test. The 6-Minute Walk Test is a sub-maximal exercise test used to assess walking endurance. A walkway of a minimum 12 m over solid flooring will be measured and marked with a turn-around marked at either end of the walkway. The turn-around points will be approximately 49 inches (124 cm) wide with clear markings. A chair will be placed at one end of the walkway to allow for seated rest breaks if necessary. Prior to administering the test, the participant will be seated in the chair resting. The participant will then be asked to walk as far as possible in 6 minutes along the walkway using scripted instruction (see below). The distance (in meters) will be calculated by multiplying the number of total laps by 12 meters and adding the distance of the partial lap completed at the time the test ended., Baseline (Pre-training), Week 2 (Post-training)|Change in NIH-EXAMINER n-back Task Accuracy, The NIH-EXAMINER assesses spatial working memory with the n-back tasks. The 1-back involves maintaining and updating one location at a time while two locations at a time are maintained and updated with the 2-back. During the n-back tasks, participants view a series of stimuli and press a button when a particular stimulus has been previously shown. The 1-back consists of one block of 30 trials, ten of which match the location of the previous square, and 20 that are in a different location. The 2-back consists of one block of 90 trials, 30 of which match the location of the square two before, and 60 that are in a different location. The score is calculated as the percentage of correct responses., Baseline (Pre-training), Week 2 (Post-training)
Secondary Outcome Measures: Change in Step Length, Gait performance is assessed with step length. Step length is the distance between heel of one foot to the heel print of the other foot, measured in feet., Baseline (Pre-training), Week 2 (Post-training)|Change in Step Length Variability, Gait performance is assessed with the variability of step length., Baseline (Pre-training), Week 2 (Post-training)|Change in De-adaptation Magnitude Assessed as Peak Step Length Symmetry, Step length symmetry data from the split-belt phase will be used to evaluate each individual's locomotor de-adaptation magnitude capacity by assessing the peak step length symmetry after treadmill belt speeds return to normal., Baseline (Pre-training), Week 2 (Post-training)|Change in De-adaptation Rate Assessed as the Number of Steps to Reach Step Symmetry, The de-adaptation rate is assessed as the number of steps required to reach a plateau in step symmetry after treadmill belt speeds return to normal., Baseline (Pre-training), Week 2 (Post-training)|Change in Timed Up and Go (TUG) Test, The Timed Up and Go test assesses mobility, balance, walking ability, and fall risk in older adults. The participant will be asked to be seated in a standard height chair (seat height 46 cm, arm height 67 cm), placing his/her back against the chair and resting his/her arms on the chair's arms. The participant will be asked to get up from the chair, walk to a line 3 m from the edge of the chair, turn around at the line, walk back to the chair, and sit down. The test will be timed using a stopwatch from when the investigator says "Go" to when the participant's buttocks touches the chair upon return. Time of the test will be recorded for single and dual-task conditions., Baseline (Pre-training), Week 2 (Post-training)
Other Outcome Measures: Change in Falls History, Falls incidence and risk is assessed as self-reported history of falls., Baseline (Pre-training), Week 2 (Post-training)|Change in Stride Duration, Gait performance is assessed as gait cycle duration, which is the time in milliseconds (ms) for the same foot to contact the floor in consecutive footsteps., Baseline (Pre-training), Week 2 (Post-training)|Change in Double-support Duration, Gait performance is assessed as double-support duration. Double-support is the time when both feet are contacting the ground and it increases as walking speed decreases., Baseline (Pre-training), Week 2 (Post-training)|Change in Executive Index Score (EIS), Cognition is assessed with the Executive Index Score (EIS) which is based on performance on Trail-Making Test Part B, Clock Drawing, Digit Span, Letter A Tapping, Serial 7 Subtraction, Letter Fluency and Abstraction items. The EIS is calculated by adding raw scores for the included tasks. Total scores range from 0 to 13 and higher scores indicate better cognitive function., Baseline (Pre-training), Week 2 (Post-training)|Change in Trail Making Test Part B Score, In Part A of the Trail Making Test (TMT) participants are presented with a sheet of paper with 25 circles numbered 1 through 25. Participants are asked to draw lines connecting the circles in ascending order of the numbers. The task is scored as the amount of time it takes in seconds for the circles to be correctly connected. The average time to complete the task is 29 seconds. Times greater than 78 seconds indicate cognitive impairment., Baseline (Pre-training), Week 2 (Post-training)