Exercise Induced Hypoalgesia in Pain-free Stroke and Healthy Populations: a Cohort Study

NCT ID: NCT07327593

Last Updated: 2026-01-08

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 60 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2026-01-31
• Study Completion Date: 2026-11-30

Brief Summary

Exercise has shown multiple beneficial effects in both healthy and post-stroke populations. One of these is the acute reduction in sensitivity to painful stimuli, called exercise-induced hypoalgesia (EIH). This phenomenon has been studied since 1979 and has shown improvements in pain thresholds with both aerobic and resistance training in healthy, pain-free populations and different chronic pain conditions.

Although there has been extensive research on EIH in healthy populations and those with chronic musculoskeletal pain, surprisingly little attention has been given to individuals with neurological pathologies. Chronic pain is found in more than 50% of patients after stroke, and 70% of affected individuals experience pain on daily activities. Reported prevalences of post-stroke pain (PSP) between different studies, but there is a general consensus that it is an underreported phenomenon. Patients with pain experience greater cognitive and functional decline, fatigue, depression and lower quality of life.

Multiple factors contribute to PSP, and various approaches exist to treat all the variables influencing it. This study aims to compare the effects of exercise on pain perception in healthy individuals and stroke patients without pain, using the same cardiovascular training protocol, to better understand the mechanisms of EIH and its maintenance after stroke, ultimately aiming to improve the treatment of people with stroke.

Conditions

Stroke; Pain; Exercise Induced Hypoalgesia

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Healthy cohort

Age > 18 years; no neurological damage; no medical conditions that could affect the test; no pain of duration > 1 week in the 3 months preceding the enrollment. No serious medical conditions.

First, pressure pain thresholds and conditioned pain modulation will be assessed. Then, participants will conduct a cardiovascular training for 30 minutes, and will be reassessed inmediately post-training and 30 minutes after.

Group Type: ACTIVE_COMPARATOR

Cardiovascular training

Intervention Type: OTHER

The cardiovascular training protocol will consist of a 5-minute warm-up aimed at reaching 70% of maximum heart rate (MHR) followed by 20 minutes of sustained work at this intensity (since maintaining this intensity is difficult, especially in the stroke cohort, we will allow for a margin of ±2-3% of MHR and provide feedback to increase or decrease the heart rate). We will aim to keep the heart rate below 73% of maximum heart rate, maintain blood pressure within safe ranges, and keep the effort level between 14/20 and 16/20

Post-stroke pain free cohort

Ischemic or hemorrhagic stroke (> 3 months); older than 18 years old; of duration > 1 week in the 3 months preceding the enrollment. No other serious medical conditions.

Post-stroke participants will get the same study protocol than healthy cohort.

Group Type: EXPERIMENTAL

Cardiovascular training

Intervention Type: OTHER

The cardiovascular training protocol will consist of a 5-minute warm-up aimed at reaching 70% of maximum heart rate (MHR) followed by 20 minutes of sustained work at this intensity (since maintaining this intensity is difficult, especially in the stroke cohort, we will allow for a margin of ±2-3% of MHR and provide feedback to increase or decrease the heart rate). We will aim to keep the heart rate below 73% of maximum heart rate, maintain blood pressure within safe ranges, and keep the effort level between 14/20 and 16/20

Interventions

Cardiovascular training

The cardiovascular training protocol will consist of a 5-minute warm-up aimed at reaching 70% of maximum heart rate (MHR) followed by 20 minutes of sustained work at this intensity (since maintaining this intensity is difficult, especially in the stroke cohort, we will allow for a margin of ±2-3% of MHR and provide feedback to increase or decrease the heart rate). We will aim to keep the heart rate below 73% of maximum heart rate, maintain blood pressure within safe ranges, and keep the effort level between 14/20 and 16/20

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Healthy cohort: Age > 18 years; no neurological damage; no medical conditions that could affect the test; no pain
• Post-stroke cohort: : Ischemic or hemorrhagic stroke (> 3 months); age > 18 years; no pain

Exclusion Criteria

• Healthy cohort: Any medical condition that could affect the test; pain in any location, of duration > 1 week in the 3 months preceding the trial.
• Post-stroke cohort: Unable to participate in the test (no possibility of transfer or active pedaling); medical contraindication to cardiovascular training for any reason; inability to follow instructions or communicate sensations during training; other neurological pathology; cardiac pathology (unstable angina, arrhythmias, aortic or left ventricular problems, myocarditis, pericarditis); pulmonary pathology that affects the test (pulmonary embolisms, pulmonary hypertension, etc.); renal or metabolic problems (severe renal dysfunction, uncontrolled diabetes, etc.); acute infection or fever; neurosurgery within 6 weeks prior to inclusion in the study; pain in any location, lasting > 1 week in the 3 months prior to the trial.; use of beta-blockers, antidepressants, or any medication that may alter heart rate measurements

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Neuron, Spain

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Alejandro Herrera Rojas, Physical Therapist

Role: PRINCIPAL_INVESTIGATOR

Neuron, Spain

Locations

Neuron Madrid Río

Madrid, Madrid, Spain

Countries

Spain

Central Contacts

Alejandro Herrera Rojas, Physical Therapist

Role: CONTACT

aherrerar2003@gmail.com

+ 34 640944777

Alfredo Lerín Calvo, Physical Therapist

Role: CONTACT

alerin@neuronrehab.es

+ 34 620187457

Other Identifiers

NeuronRehab

Identifier Type: -

Identifier Source: org_study_id