AMPLIFI: Adaptive Modulation of Plasticity Through Lactate and Fitness Interventions

Summary

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.

Conditions

• Stroke, Chronic
• Aging
• Cognitive Decline
• Motor Dysfunction
• Neuroplasticity

Interventions

BEHAVIORAL

High intensity cycling

Participants cycle on a stationary ergometer at an intensity prescribed to reach their lactate threshold, guided by VO2 max results and lactate sampling. The session lasts approximately 20 minutes and is preceded and followed by TMS assessments and a structured motor learning task. This condition is designed to evaluate the effect of exercise-induced metabolic stress on cortical inhibition and motor learning.

BEHAVIORAL

Low-intensity cycling

Participants perform 20 minutes of cycling at a light workload below their lactate threshold. Exercise intensity is individualized using heart rate and perceived exertion (Borg RPE scale), avoiding significant metabolic activation. TMS and motor learning are assessed pre- and post-exercise. This condition serves as an active comparator to assess the impact of exercise intensity.

BEHAVIORAL

Health education session

Participants receive a 20-minute session of health education content (e.g., wellness, healthy aging). No exercise is performed. Participants undergo TMS and motor learning testing before and after the session. This condition is used to control for attention and cognitive engagement without physical activity.

BEHAVIORAL

Moderate Intensity Aerobic Exercise

Participants cycle on a stationary ergometer at an intensity prescribed to surround, but not exceed their lactate threshold, guided by VO2 max results and lactate sampling. The session lasts approximately 20 minutes and is preceded and followed by TMS assessments and a structured motor learning task. This condition is designed to evaluate the effect of moderate exercise-induced metabolic stress on cortical inhibition and motor learning.

Sponsors & Collaborators

• University of Alabama at Birmingham

  lead OTHER

Principal Investigators

• Keith McGregor, PhD · Keith McGregor

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-05-14

Primary Completion

2029-09-01

Completion

2030-01-01

Countries

• United States

Study Locations