Disentangling the Variability of Exercise-induced Hypoalgesia: the Role of Circulatory Compounds

Launched by UNIVERSITÉ CATHOLIQUE DE LOUVAIN · May 12, 2025

Keywords

ClinConnect Summary

This clinical trial is exploring how physical exercise can help reduce pain sensitivity, a phenomenon known as exercise-induced hypoalgesia (EIH). Researchers want to understand the biological processes behind this effect and whether they can vary from person to person. To do this, they will invite 90 healthy adults aged 18 to 30 years to participate in the study, during which they will cycle for 25 minutes. Participants will have their pain sensitivity tested before, immediately after, and 45 minutes after exercising, as well as provide blood samples to measure specific compounds that may influence pain sensitivity.

To be eligible for the study, participants must be either male or female (if using hormonal contraception for at least three months), aged 18 to 30, and have a body mass index (BMI) between 17 and 30. They should not have any chronic pain conditions, recent surgeries, or certain medical issues. Participants will need to avoid alcohol, recreational drugs, and certain foods before testing sessions and will be asked to remain sedentary for 24 hours prior to their exercise session. This study could provide valuable insights into how exercise affects pain perception and whether there are differences based on gender.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Males, or females using hormonal contraception since ≥ 3 months.
• • Aged between 18 and 30 years.
• • Ability to provide written informed consent.
• • Fluency in French or English.
• • BMI between 17 and 30 kg/cm2.
• Exclusion Criteria:
• • Regular tobacco use (\> 1/month)
• • 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 evidence for neurological, cardiovascular, respiratory, inflammatory, endocrine, psychiatric, oncological, rheumatological conditions on direct questioning.
• • 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 preceding 2 years).
• • Wounds or skin alteration on testing sites.
• • 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.
• • Pregnancy.