AMPLIFI: Adaptive Modulation of Plasticity Through Lactate and Fitness Interventions
试验速览
- 阶段
- 不适用
- 状态
- 进行中（未招募）
- 入组人数
- 48
- 试验地点
- 2
- 主要终点
- Motor Learning Performance (12-Digit Serial Reaction Time Task)
研究概览
简要总结
The AMPLIFI study (Adaptive Modulation of Plasticity through Lactate and Fitness Interventions) investigates how short-term aerobic exercise influences brain plasticity and learning in older adults and stroke survivors. The study compares three groups: one performing aerobic cycling at an intensity that elevates lactate levels, one performing low-intensity exercise, and one receiving health education without exercise.
All participants will complete motor learning tasks and undergo brain-stimulation testing using transcranial magnetic stimulation (TMS) to assess how well the brain responds to training. The goal is to understand whether different types of exercise can improve brain function, movement, and memory, and how the body's response to exercise (like lactate levels) might support brain health.
This research may help identify low-cost, non-invasive interventions-such as targeted exercise-that improve motor and cognitive outcomes in aging and stroke recovery.
详细描述
The AMPLIFI study is a mechanistic clinical trial designed to investigate the neurophysiological effects of acute aerobic exercise on cortical plasticity and motor learning in older adults and individuals with chronic stroke. Participants are randomized into one of three groups: (1) moderate-to-high intensity aerobic exercise at lactate threshold, (2) moderate intensity aerobic exercise, (3) low-intensity aerobic exercise, or (4) education-only control.
The primary outcome measure is cortical inhibition, assessed using transcranial magnetic stimulation (TMS) measures including short-interval intracortical inhibition (SICI), long-interval intracortical inhibition (LICI), and intracortical facilitation (ICF). Secondary outcomes include performance on upper extremity motor tasks, measures of verbal and executive function, and blood lactate levels.
Participants complete three sessions over 2-3 weeks, including baseline assessments, VO2 max testing, multiple blood draws, and cognitive and motor testing. The exercise intervention is delivered via stationary cycling at intensities tailored using individual VO2 max data and lactate monitoring. Genetic and biochemical assays will be performed on blood samples to explore associations between metabolic and neural response.
This study will clarify how lactate-related exercise intensity impacts cortical inhibition and whether those effects support improvements in motor learning. Findings may help define the mechanisms by which exercise promotes neuroplasticity and support individualized rehabilitation strategies for aging and post-stroke populations.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 85 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •For All Participants:
- •Able to provide informed consent
- •Right-handed (for TMS consistency)
- •English-speaking
- •Clearance for moderate-intensity aerobic exercise
- •Able to safely sit and pedal a stationary cycle ergometer
- •No contraindications to TMS (e.g., no metal in skull, pacemakers, or seizure history)
- •Younger Adults (18-35):
- •No history of neurological or psychiatric conditions
- •Not currently on medications that affect the central nervous system
- •Older Adults (60-85):
- •No diagnosis of dementia
- •Independent in activities of daily living
- •No stroke history
- •Stroke Survivors (40-85):
- •At least 6 months post-stroke (chronic phase)
- •Medically stable and cleared for aerobic exercise
- •Able to engage in motor learning task (with or without hemiparetic adaptations)
排除标准
- •History of epilepsy or seizures
- •Current substance abuse or uncontrolled psychiatric disorder
- •Severe cardiovascular disease or unstable medical condition
- •Pregnancy
- •Contraindications to TMS or exercise testing (e.g., implanted neurostimulators, severe hypertension)
- •Participation in another interventional trial within the past 30 days
研究组 & 干预措施
Low-Intensity Aerobic Exercise
Participants complete a 20-minute cycling session at a light workload, below lactate threshold. This condition controls for movement and engagement without significant metabolic challenge. TMS and motor learning outcomes are assessed pre- and post-intervention.
干预措施: Low-intensity cycling (Behavioral)
Education Control
Participants engage in a 20-minute health education session instead of exercise. This arm serves as a non-exercise control to isolate the effects of physical exertion on neuroplasticity. All outcome measures are collected similarly to the exercise groups.
干预措施: Health education session (Behavioral)
Aerobic Exercise at Lactate Threshold
Participants complete a 20-minute aerobic cycling session at individually prescribed intensity to achieve lactate threshold, based on VO2 max and blood lactate data. This condition is designed to induce metabolic stress and engage neuromodulatory pathways related to cortical plasticity. Participants complete TMS and motor learning tasks before and after the intervention.
干预措施: High intensity cycling (Behavioral)
Active Comparator: Moderate-Intensity Aerobic Exercise
Arm Description: Participants complete a 20-minute cycling session at a moderate workload, surrounding lactate threshold. This condition controls for movement and engagement without advanced metabolic challenge. TMS and motor learning outcomes are assessed pre- and post-intervention.
干预措施: Moderate Intensity Aerobic Exercise (Behavioral)
结局指标
主要结局
Motor Learning Performance (12-Digit Serial Reaction Time Task)
时间窗: Baseline, Day 2, Day 3, Day 4, and Day 5
Motor learning is assessed using the 12-digit Serial Reaction Time Task (SRTT), a computer-based measure of implicit motor sequence learning. Participants respond to visual cues by pressing buttons in a fixed or random sequence. Learning is quantified by changes in reaction time and accuracy across structured and unstructured trials. A learning index is derived by comparing performance between patterned (learning) and random sequences.
次要结局
- Change in Long-Interval Intracortical Inhibition (LICI)(Baseline, Day 5)
- Change in Intracortical Facilitation (ICF)(Baseline, Day 5)
- Change in Blood Lactate Concentration(Day 2, Day 3, Day 4)
- Change in Executive Function (D-KEFS Verbal Fluency and Stroop Tests)(Day 1 and Day 5)
研究者
Keith McGregor
Associate Professor, Director of Research
University of Alabama at Birmingham