Mechanisms of Exercise-induced Hypoalgesia

Université Catholique de Louvain

Status: Completed

Conditions: Healthy; Men; Adults

Treatments: Behavioral: Cycling exercise; Behavioral: Cycling control

Study type: Interventional

Funder types: Other

Identifiers

NCT05961449

EIH

Details and patient eligibility

About

This project aims to clarify the mechanisms underpinning the acute analgesic effect of exercise in healthy humans-a phenomenon called "Exercise-induced hypoalgesia" (EIH). This study will characterize, using a within-subject cross-over design, the effects of a single session of aerobic exercise vs. a control condition on the sensitivity to stimuli preferentially activating mechano vs. heat-sensitive nociceptors of the skin vs. muscle, within vs. outside exercising body parts. The investigators hypothesize (1) that EIH will be greater in the exercise session compared to the control session, (2) that EIH will be greater at the local site compared to the remote site if local changes in nociceptive sensitivity contribute to EIH, and (3) that exercise will preferentially affect blunt pressure-induced pain if EIH involves specific changes in sensitivity of muscle nociceptors.

Enrollment: 40 patients

Sex: Male

Ages: 18 to 30 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Males aged between 18 and 30 years
• Lack of risks for physical exercise assessed using the Physical Activity Readiness Questionnaire (PAR-Q)
• Ability to provide written informed consent
• Fluency in French
• BMI between 17 and 30

Exclusion criteria

• Regular tobacco use
• Not willing or able to abstain from alcohol, recreational drugs, coffee, or tea from 24 hours prior to each experimental session.
• Not willing or able to restrain from physical activity > 24h prior to each experimental session, and to be in a fasted state on the day of each experimental session.
• Any neurological, cardio-vascular, respiratory, inflammatory, endocrine, psychiatric, oncological, rheumatological conditions. Such condition could put the participants at risk during maximal exercise testing and/or interfere with pain assessment.
• Presence of any medical devices (e.g., cardiac pacemaker) implants or prothesis unless it is beyond discussion that these will not put the subject's safety during the study at risk and will not interfere with the results of the study.
• Any chronic pain condition or recent history thereof (i.e. within the preceeding 2 years).
• Wounds or skin alteration on testing sites.
• Impaired hearing. This would affect ability to detect the control auditory stimuli.
• Surgery < 12 months
• Any drug intake in the past 2 weeks including antibiotics, herbal medicines and other remedies except the following drugs that will be allowed up to 48 hours prior to the experiments: oral paracetamol or ibuprofen for a self-limiting condition (e.g. toothache, bruise). Oral antihistaminics and nasal aerosol and topical treatments for seasonal allergy up to 1 week before the experimental session.
• Any physical activity contraindication

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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40 participants in 2 patient groups

Experimental condition

Experimental group

Description:

Participants will complete an experimental exercise that will consist in 25 minutes of cycling between 60-80 Revolution Per Minute (RPM) on a cycle ergometer (CST BX40; Cardiostrong; Germany) at ≥ 70% of the Heart Rate Reserve (HRR).

Treatment:

Behavioral: Cycling exercise

Control condition

Sham Comparator group

Description:

The control condition will include an exercise design similar to the experimental condition except that the resistance will be kept at 25 W and the RPM below 50. The intensity of the exercise will be kept at minimal levels by ensuring that the heart rate does not increase \>25% from baseline

Treatment:

Behavioral: Cycling control