Acute Sauna Session and Glucose Control

The Effects of an Acute Sauna Session on Glucose Control in Individuals at Risk for Metabolic Impairments

The goal of this clinical trial is to examine the effect of a single 40-minute sauna session on glucose control in individuals at risk for metabolic impairments.

Research Questions:

• Can a single sauna session completed before a meal reduce the post-meal blood glucose response?
• Can a single sauna session improve 24-hour glucose control?

Study Design:

Participants will complete two lab visits: one involving a sauna session and one placebo visit (resting condition). Researchers will compare the effects on glucose control using a continuous glucose monitor (CGM).

What Participants Will Do:

Attend a sauna familiarization session Have a CGM sensor placed on the upper arm Visit the lab twice (once for sauna, once for placebo) Consume three standardized meals at home after each session

Study Overview

• Status: Recruiting
• Conditions: Obesity & Overweight
• Intervention / Treatment: Other: Infrared sauna session; Other: Resting condition

Detailed Description

At least 72 hours prior to the first trial, participants will complete a familiarization session consisting of two 20-minute infrared sauna exposures. The study employs a randomized crossover design, with each participant completing both experimental conditions-infrared sauna (two 20-minute sessions at 175°F / 79°C, separated by a 5-minute break) and seated rest (two 20-minute periods of quiet sitting, separated by a 5-minute break)-separated by at least 72 hours. On each trial day, participants will arrive at the laboratory at 7:50 a.m. after an overnight fast from 8:00 p.m., with water permitted throughout. Participants will wear a continuous glucose monitor (CGM) during both trial days. Baseline measurements of blood pressure, heart rate, and oral body temperature will be recorded, and food logs reviewed. Following the condition session, a sedentary recovery period will occur until 9:45 a.m., with repeated physiological measurements. Final measurements of blood pressure, heart rate, and oral body temperature will be collected prior to a standardized breakfast provided from 9:45 to 10:10 a.m. Participants will depart thereafter by car or public transportation and remain sedentary for the remainder of the day. Meals for the rest of the day, i.e., breakfast, lunch, dinner, and a bedtime snack, will be provided and identical across trial days. Participants will fast again from 9:00 p.m. until 9:00 a.m. the following morning.

• Study Type: Interventional
• Enrollment (Estimated): 15
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Etienne Myette-Cote, PhD; Phone Number: 9025660756; Email: emyette-cote@upei.ca
• Study Contact Backup: Name: Romina Babazadeh, MSc; Phone Number: 9026205034; Email: rbabazadeh@upei.ca

Study Locations

• Canada
  • Prince Edward Island
    • Charlottetown, Prince Edward Island, Canada, C1A 4P3
      • Recruiting
      • University of Prince Edward Island
      • Contact: Etienne Myette-Cote, PhD; Phone Number: 9026550756; Email: emyette-cote@upei.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Are 30-55 years old

Have a body mass index of ≥ 27 kg/m2

Have a waist size >102 cm (men) or >88 cm (women)

Have access to transportation for the 2 experimental visits (e.g., car, public transit, or drop-off).

Are cleared for participation based on the Physical Activity Readiness Questionnaire (PAR-Q+).

Exclusion Criteria:

Take medications that affect blood sugar

Exercise intensely 2+ times/week

Have diabetes, heart issues, low blood sugar or pressure

Are pregnant

Regularly use saunas or other heat therapy 1+ times/week

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Sauna; Infrared sauna session	Other: Infrared sauna session; Infrared sauna session (approximately 165°F; two 20-minute sessions separated by a 5-minute rest outside the sauna)
Placebo Comparator: Resting control; Seated resting session	Other: Resting condition; Seated resting session (45 minutes outside the sauna)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incremental 2-hour postprandial glucose area under the curve (Breakfast)	2-hour postprandial incremental AUC of CGM glucose above baseline, measured after the standardized breakfast consumed 45 minutes following the sauna or resting (control) session.	2 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
2-hour postprandial glucose area under the curve (Breakfast)	2-hour postprandial AUC of CGM glucose above baseline, measured after the standardized breakfast consumed 45 minutes following the sauna or resting (control) session.	2 hours
Incremental 2-hour postprandial glucose area under the curve (Lunch)	Incremental 2-hour postprandial AUC of CGM glucose above baseline, measured after the standardized lunch consumed 225 minutes following the sauna or resting (control) session.	2 hours
Incremental 2-hour postprandial glucose area under the curve (Dinner)	Incremental 2-hour postprandial AUC of CGM glucose above baseline, measured after the standardized lunch consumed 435 minutes following the sauna or resting (control) session.	2 hours
Incremental 2-hour postprandial glucose area under the curve (Bedtime snack)	Incremental 2-hour postprandial AUC of CGM glucose above baseline, measured after the standardized lunch consumed 645 minutes following the sauna or resting (control) session.	2 hours
Average incremental 2-hour postprandial glucose area under the curve (4 meals)	Average incremental 2-hour postprandial CGM glucose AUC above baseline, measured after each standardized meal consumed following the sauna or resting (control) session. The incremental AUC for all four meals will be summed and divided by four to calculate the average incremental postprandial response.	2 hours
Time below range	Total time (minutes) during which CGM glucose values remained below 3.9 mmol/L over the 24-hour period following the sauna or resting (control) session.	24 hours
Time above range	Total time (minutes) during which CGM glucose values remained above 7.8 mmol/L over the 24-hour period following the sauna or resting (control) session.	24 hours
Time in range	Total time (minutes) during which CGM glucose values remained between 3.9 and 7.8 mmol/L over the 24-hour period following the sauna or resting (control) session.	24 hours
Session-induced delta glucose	Change in CGM glucose during the 45-minute sauna or resting (control) session, calculated as the difference between post-session and pre-session values (Δ = post - pre).	45 minutes
Fasting glucose	CGM glucose representing fasting levels the morning after the sauna or resting (control) session, computed as the mean glucose over the 15 minutes preceding the standardized breakfast.	15 minutes
Daily mean glucose	CGM glucose average over the 24h period following the sauna or resting (control session).	24 hours

Collaborators and Investigators

• Sponsor: University of Prince Edward Island
• Collaborators: DexCom, Inc.
• Investigators: Principal Investigator: Etienne Myette-Cote, University of Prince Edward Island

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2025
• Primary Completion (Estimated): December 15, 2026
• Study Completion (Estimated): April 15, 2027

Study Registration Dates

• First Submitted: April 2, 2026
• First Submitted That Met QC Criteria: April 2, 2026
• First Posted (Actual): April 9, 2026

Study Record Updates

• Last Update Posted (Actual): April 9, 2026
• Last Update Submitted That Met QC Criteria: April 2, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: obesity; overweight; continuous glucose monitoring; sauna; heat-therapy
• Additional Relevant MeSH Terms: Wounds and Injuries; Nutrition Disorders; Overnutrition; Body Weight; Body Temperature Changes; Heat Stress Disorders; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Hyperthermia; Overweight; Obesity
• Other Study ID Numbers: UPrinceEdwardIsland

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No