Effects of Hot Baths Prior or After a Damaging Protocol on Muscle Function and HSP70 Expression (Prehotemp)

Muscle lengthening contractions lead to physiological responses such as strength loss, soreness, immune cell infiltration, and CK production, along with elevated heat shock proteins (HSPs), which protect and regenerate cells. Passive heating before or after exercise can aid in recovery by restoring strength and reducing soreness, requiring a core temperature of over 38.5°C for 20 minutes to be effective. Studies show that combined mechanical and thermal stress induces a cumulative HSP response, enhancing cellular protection. Thermal stress alone peaks at 16- 24 hours, whereas mechanical stress shows a biphasic response, with peaks at 3-6 hours and around 39 hours. Thus, combining heat with exercise could optimize HSP production, improving recovery by increasing and accelerating the HSP response. However, more research is needed to determine the best timing for thermal stress in human applications, especially in sports and therapy contexts.

This study aimed to compare the effects of hot-water immersion administered before versus after muscle-lengthening exercise on muscle function and HSP70 expression in healthy young athletes.

Study Overview

• Status: Recruiting
• Conditions: Recovery; Heat Stress; Mechanical Stress; HSP70; Cumulative Response; Hot-water Immersion
• Intervention / Treatment: Other: Immersion; Other: NIRS; Other: isokinetic dynamometer; Other: pressure algometer; Other: Hokanson armband

• Study Type: Interventional
• Enrollment (Estimated): 96
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Yannis Hamidou, MD; Phone Number: 33+3 22 66 82 48; Email: Hamidou.yannis@chu-amiens.fr

Study Locations

• France
  • Amiens, France, 80054
    • Recruiting
    • CHRU Amiens
    • Contact: Yannis Hamidou, MD; Phone Number: 33+3 22 66 82 48; Email: Hamidou.yannis@chu-amiens.fr

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Sex: Healthy, athletic men practicing track and field (10 to 12 hours/week)
• Age: 19 to 25 years old
• Social security coverage
• Signed informed consent

Exclusion Criteria:

• Age over 26 years
• Low level of physical activity (less than 8 hours per week)
• Recent sprain (type 1, 2, or 3) or ligament rupture in the lower limb (within the last 8 months)
• Exposure to an altitude of 2500m within 15 days prior to the protocol
• Presence of arterial hypotension:
• Systolic blood pressure below 90 mmHg
• Diastolic blood pressure below 60 mmHg
• A drop in systolic blood pressure greater than 20 mmHg upon moving from a lying to a standing position.
• A drop in diastolic blood pressure greater than 10 mmHg upon moving from a lying to a standing position.
• Presence of dizziness, lightheadedness, or blurred vision upon moving from a lying to a standing position.
• Participant under guardianship/conservatorship or deprived of liberty.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 41 pre-EIMD; hot-water immersion at 41°C performed 24 hours before EIMD (pre-EIMD)	Other: Immersion; Immersion lasted 40 minutes with the goal of reaching a core temperature of 38.5°C in the heat-stress groups; Other: NIRS; NIRS; Other: isokinetic dynamometer; isokinetic dynamometer; Other: pressure algometer; pressure algometer; Other: Hokanson armband; Hokanson armband
Experimental: 41 post-EIMD; hot- water immersion at 41°C immediately after EIMD (post-EIMD)	Other: Immersion; Immersion lasted 40 minutes with the goal of reaching a core temperature of 38.5°C in the heat-stress groups; Other: NIRS; NIRS; Other: isokinetic dynamometer; isokinetic dynamometer; Other: pressure algometer; pressure algometer; Other: Hokanson armband; Hokanson armband
Sham Comparator: 36°C post- EIMD; sham immersion at 36°C post- EIMD	Other: Immersion; Immersion lasted 40 minutes with the goal of reaching a core temperature of 38.5°C in the heat-stress groups; Other: NIRS; NIRS; Other: isokinetic dynamometer; isokinetic dynamometer; Other: pressure algometer; pressure algometer; Other: Hokanson armband; Hokanson armband

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HSP 70 concentration	HSP 70 concentration in third groups	1 year

Secondary Outcome Measures

Outcome Measure	Time Frame
gastro-intestinal temperature	1 year
muscle temperature	1 year

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire, Amiens
• Collaborators: CH CORBIE

Study record dates

Study Major Dates

• Study Start (Actual): February 16, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): February 1, 2027

Study Registration Dates

• First Submitted: April 7, 2026
• First Submitted That Met QC Criteria: April 23, 2026
• First Posted (Actual): April 30, 2026

Study Record Updates

• Last Update Posted (Actual): April 30, 2026
• Last Update Submitted That Met QC Criteria: April 23, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Recovery; HSP70; heat stress; mechanical stress; cumulative response; hot-water immersion
• Additional Relevant MeSH Terms: Wounds and Injuries; Heat Stress Disorders; Investigative Techniques; Immersion
• Other Study ID Numbers: PI2025_843_0182

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