Effects of melatonin on heart responses during exercise and cold exposure

The Effects of Acute Melatonin Supplementation on Cardiovascular Responses to Sympathetic Activation

PHASE4 · University of Oklahoma · NCT04831398

This study is testing if taking melatonin can change how the heart responds during exercise and when exposed to cold in people who participate.

Quick facts

PhasePHASE4
Study typeInterventional
Enrollment100 (estimated)
Ages18 Years to 35 Years
SexAll
SponsorUniversity of Oklahoma (other)
Locations1 site (Norman, Oklahoma)
Trial IDNCT04831398 on ClinicalTrials.gov

What this trial studies

This experiment aims to investigate how acute melatonin supplementation influences cardiovascular responses during sympathetic activation, specifically through a cold pressor test and dynamic exercise. Participants will undergo three visits, including a screening and two experimental sessions where they will receive either melatonin or a placebo in a randomized, single-blind design. Measurements will be taken at rest and during exercise to assess changes in cardiovascular function. The study is conducted at the University of Oklahoma's Human Circulation Research Laboratory.

Who should consider this trial

Good fit: Ideal candidates are healthy premenopausal men and women with regular menstrual cycles.

Not a fit: Patients with cardiovascular diseases, diabetes, or those using tobacco/nicotine will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide insights into how melatonin affects cardiovascular health during stress conditions.

How similar studies have performed: While the effects of melatonin on sleep and circadian rhythms are well-documented, this specific approach to cardiovascular responses during sympathetic activation is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Healthy men and women
* Women must be premenopausal with a regular menstrual cycle (26-30 days)

Exclusion Criteria:

* History of autonomic dysfunction
* Cardiovascular diseases
* Diabetes
* Tobacco/nicotine use
* Systolic Pressure \>= 130 mmHg
* Diastolic Pressure \>= 85 mmHg
* Regular melatonin use \>= 1 use/week
* Allergy to melatonin
* Cardiometabolic medication use (e.g. anti-hypertensives, insulin-sensitizing, statins)
* Sex hormone replacement medical use (e.g. testosterone, estrogen, progesterone)
* Pregnancy

Where this trial is running

Norman, Oklahoma

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Healthy

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.