Core Temperature in Open Water Wetsuited Swimming.

NCT06685627 | Completed

• 1 other identifier: Akershus Universitetssykehus
• Study Type: observational
• Target: 36
• Locations: 1 country
• Sites: 1

Brief Summary

Swimming in cold water is intrinsically unsafe. One of the threats is a fall in core body temperature (Tcore), which adversely affects all body systems and increases the risk of death. Wetsuits mitigate, but do not negate this threat. Environmental conditions may confound findings from laboratory studies or computer models, thus necessitating open water studies. This study was designed to investigate the effects of open water wetsuited swimming on core body temperature at a range of different water temperatures between 8.4oC and 24.5oC.

Conditions

Temperature

Keywords

Core temperature; water; swim; wetsuit; cold

Outcome Measures

Primary Outcomes (1)

• Core temperature

  A self-inserted rectal pill was used to continuously measure core temperature in 76 open water swims by 31 wetsuited swimmers in water temperatures ranging from 8.4°C to 24.5°C. The Tcore curves were analysed by linear mixed model regression.

  The thermistor was inserted 15 minutes prior to immersion and measured the core temperature until 30 minutes after egress from the water.

Interventions

Open water wetsuited swimming. OTHER

All swimmers used their own well-fitting wetsuits (5 mm maximum thickness in accordance with World Triathlon guidelines7) and were free to supplement additional neoprene hats, gloves and booties as desired. A safety paramedic attended all swims. Swim distance was self-determined

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Trained and highly trained swimmers were recruited from local swim clubs and via social media

You may qualify if:

• Trained and highly trained swimmers.

You may not qualify if:

• a history of cardiovascular disease, arrhythmias, or gastrointestinal abnormalities precluding the use of rectal temperature measurement.

Sponsors & Collaborators

• University Hospital, Akershus: lead
• Oslo University Hospital: collaborator
• Norwegian Armed Forces Medical Service: collaborator
• SINTEF MiNaLab: collaborator

Study Sites (1)

Institute of Clinical Medicine, University of Oslo, Oslo, Norway

Olso, Olso, Norway

Location

Related Publications (1)

• Morton WJ, Melau J, Olsen RA, Lovvik OM, Hisdal J, Sovik S. Thermal physiology of open water wetsuited swimming: A cohort study. Temperature (Austin). 2025 Mar 24;12(3):245-263. doi: 10.1080/23328940.2025.2479893. eCollection 2025.

  PMID: 40926792 DERIVED

MeSH Terms

Conditions

Common Cold

Condition Hierarchy (Ancestors)

Respiratory Tract Infections; Infections; Picornaviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases

Study Officials

• Jonny Hisdal, PhD

  Institute of Clinical Medicine, University of Oslo, Oslo, Norway

  STUDY DIRECTOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principle Investigator

Study Record Dates

• First Submitted: November 11, 2024
• First Posted: November 12, 2024
• Study Start: October 27, 2015
• Primary Completion: October 18, 2020
• Study Completion: October 18, 2020
• Last Updated: November 12, 2024

Record last verified: 2024-11

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Time Frame: IPD and supporting data will be available from publication of the primary outcome data in a peer review journal and will be supported for 10 years form that date.
• Access Criteria: IPD will be shared upon request from a validated body and subject to a data sharing agreement with the University of Oslo.

Locations

NO (1)