Healthy, Young Adults
Conditions
Keywords
ischemic conditioning, motor learning, strength, cognition
Brief summary
The purpose of this research study is to determine if remote limb ischemic conditioning (RLIC) can enhance learning of a motor (balance) and an ecologically valid, complex cognitive-motor (driving) task, and increase skeletal muscle strength in neurologically-intact young adults.
Detailed description
Ischemic conditioning is an endogenous phenomenon in which exposing a target organ or tissue to one or more brief episodes of ischemia results in protection of that organ against subsequent ischemia. The effects of ischemic conditioning are not confined within an organ but can be can be transferred from one organ to another, a technique called remote ischemic conditioning. A clinically feasible method for this is remote limb ischemic conditioning (RLIC), where episodes of ischemia and perfusion are induced with a blood pressure cuff placed on the arm. The overall goal of this line of work is to use ischemic conditioning to enhance learning and outcomes in persons with neurologic injuries. Two previous studies have shown that remote limb ischemic conditioning (RLIC) can enhance learning a motor task in healthy young adults. The current study extends that work to determine if RLIC enhances muscle strength training and a complex cognitive-motor task (simulated driving). This Phase I study will yield the necessary information to design and execute subsequent trials in neurologic patient populations.
Interventions
BEHAVIORALRLIC
See descriptions under arm/group descriptions. RLIC is delivered for 8 visits. Visits 1-3 occur on consecutive work days and visits 4-8 occur on alternating week days.
BEHAVIORALSham conditioning
See descriptions under arm/group descriptions. Sham conditioning is delivered for 8 visits. Visits 1-3 occur on consecutive work days and visits 4-8 occur on alternating week days.
BEHAVIORALMuscle strength training
All participants undergo muscle strength training of the wrist extensor muscles on one side. Strength training follows standard American College of Sports Medicine guidelines for frequency, intensity, progression etc. Strength training is provided at visits 3-8
BEHAVIORALDriving training
All participants undergo training of a complex cognitive-motor task using a driving simulator. Participants learn to 'drive' on a virtual course, maximizing speed and minimizing errors. Participants perform the driving task once each day for visits 3-8.
BEHAVIORALBalance training
All participants undergo training on a balance board, learning to hold the board level with equal weight on each leg. Participants perform the balance task for 15, 30-second trials per day at visits 3-8.
Sponsors
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Washington University School of Medicine
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Masking description
Participants are masked to group assignment (RLIC vs. Sham conditioning).
Intervention model description
Single blinded, randomized controlled trial
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
1. Healthy adults between the age of 18 and 40 years 2. Visual acuity of 20/20 with corrected vision
Exclusion criteria
1. History of neurological condition (i.e. stroke, Alzheimer's disease, Parkinson's disease), Attention Deficit Hyperactivity Disorder (ADHD), depression, bipolar disorder, balance impairment, or vestibular disorder 2. History of severe motion sickness, moderate to severe motion sickness or nausea on oculo-motor components of Simulator sickness questionnaire, inability to ride a car, boat, train or airplane due to motion sickness 3. Recent wrist, hand or forearm injury that would currently prevent ability to lift weights 4. History of lower extremity condition, injury, or surgery that would currently impair ability to stand or balance 5. Any extremity soft tissue, orthopedic, or vascular injury (i.e. peripheral vascular disease) which may contraindicate RLIC 6. Any cognitive, sensory, or communication problem that would prevent completion of the study 7. History of or current sleep apnea 8. Current intensive weight lifting or interval training exercise 9. Current substance abuse or dependence 10. Unwillingness to travel for all study visits
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| One-repetition Maximum of Wrist Extensors | Pre-intervention, post-intervention (2 weeks later), and 1 month post-intervention follow-up | The maximum amount of force (lbs) that a participant can generate while performing one wrist extension movement. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Remote Limb Ischemic Conditioning (RLIC) RLIC is achieved via blood pressure cuff inflation to 20 mmHg above systolic blood pressure on the dominant arm. RLIC requires 45 minutes and involves 5 cycles of 5 minutes blood pressure cuff inflation followed by alternating 5 minutes of cuff deflation. RLIC is performed on visits 1-8.
RLIC is delivered for 8 visits. Visits 1-3 occur on consecutive work days and visits 4-8 occur on alternating week days.
Muscle strength training: All participants undergo muscle strength training of the wrist extensor muscles on one side. Strength training follows standard American College of Sports Medicine guidelines for frequency, intensity, progression etc. Strength training is provided at visits 3-8 | 15 |
| Sham Conditioning Sham conditioning is achieved via blood pressure cuff inflation to 10 mmHg under diastolic blood pressure on the dominant arm. Sham conditioning requires 45 minutes and involves 5 cycles of 5 minutes blood pressure cuff inflation followed by alternating 5 minutes of cuff deflation. Sham conditioning is performed on visits 1-8.
Sham conditioning is delivered for 8 visits. Visits 1-3 occur on consecutive work days and visits 4-8 occur on alternating week days.
Muscle strength training: All participants undergo muscle strength training of the wrist extensor muscles on one side. Strength training follows standard American College of Sports Medicine guidelines for frequency, intensity, progression etc. Strength training is provided at visits 3-8 | 15 |
| Total | 30 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Protocol Violation | 2 | 0 |
| Overall Study | Withdrawal by Subject | 2 | 0 |
Baseline characteristics
| Characteristic | Remote Limb Ischemic Conditioning (RLIC) | Sham Conditioning | Total |
|---|---|---|---|
| Age, Continuous | 25.5 years STANDARD_DEVIATION 3.8 | 27.3 years STANDARD_DEVIATION 4.3 | 26.4 years STANDARD_DEVIATION 4.1 |
| BMI | 22.6 kg/m*m STANDARD_DEVIATION 3.1 | 24.6 kg/m*m STANDARD_DEVIATION 3.9 | 23.6 kg/m*m STANDARD_DEVIATION 3.5 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 5 Participants | 4 Participants | 9 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 2 Participants | 3 Participants |
| Race (NIH/OMB) More than one race | 1 Participants | 1 Participants | 2 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 8 Participants | 8 Participants | 16 Participants |
| Region of Enrollment United States | 15 Participants | 15 Participants | 30 Participants |
| Sex: Female, Male Female | 10 Participants | 10 Participants | 20 Participants |
| Sex: Female, Male Male | 5 Participants | 5 Participants | 10 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 19 | 0 / 15 |
| other Total, other adverse events | 0 / 19 | 0 / 15 |
| serious Total, serious adverse events | 0 / 19 | 0 / 15 |
Outcome results
Primary
One-repetition Maximum of Wrist Extensors
The maximum amount of force (lbs) that a participant can generate while performing one wrist extension movement.
Time frame: Pre-intervention, post-intervention (2 weeks later), and 1 month post-intervention follow-up
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Remote Limb Ischemic Conditioning (RLIC) | One-repetition Maximum of Wrist Extensors | Pre | 22.6 lbs | Standard Deviation 10.3 |
| Remote Limb Ischemic Conditioning (RLIC) | One-repetition Maximum of Wrist Extensors | Post | 32.0 lbs | Standard Deviation 14 |
| Remote Limb Ischemic Conditioning (RLIC) | One-repetition Maximum of Wrist Extensors | Follow-up | 30.8 lbs | Standard Deviation 13.4 |
| Sham Conditioning | One-repetition Maximum of Wrist Extensors | Pre | 23.7 lbs | Standard Deviation 7.9 |
| Sham Conditioning | One-repetition Maximum of Wrist Extensors | Post | 29.9 lbs | Standard Deviation 10.8 |
| Sham Conditioning | One-repetition Maximum of Wrist Extensors | Follow-up | 29.2 lbs | Standard Deviation 10.5 |
Comparison: Mixed model ANOVA with group (RLIC, Sham) and time (pre-, post-, and follow-up ). The main analysis of interest is the group x time interaction from pre- to post-.p-value: 0.002ANOVA
p-value: 0.001ANOVA
p-value: 0.844ANOVA