Hypothermia
Conditions
Brief summary
A significant medical risk associated with hypothermia during exercise in a cold environment cardiac arrhythmia due to a possible autonomic conflict. However, little is known about the changes in heart rate and cardiac function after prolonged cold water swimming. The investigators propose to measure the changes in core temperarure during and after a cold water swim at at a water temperature below 15.5°C qualifying for English Channel swim and to test the association with changes in heart rate variability, resting electrocardiogram and left ventricle function.
Interventions
None listed
Sponsors
University Hospital, Caen
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Inclusion criteria
* swimmers taking part in the Channel Swim Camp * swimmers above 18 years of age * swimmers willing and able to give informed consent for participation in the study
Exclusion criteria
* swallowing disorder * chronic gastrointestinal disease * MRI scheduled within 48 hours after the race. * known cardiac arythmia or cardiovascular disease
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Heart rate from a resting ECG recording | Two Time points (1) the day before the race and (2) at 30 min after ending the race | Waves, intervals & segments of the normal ECG trace was collected |
| Heart rate from a 5-minute ECG recording | Two Time points (1) the day before the race and (2) at 30 min after ending the race | Heart rate variability (HRV) parameters including time-domain measures and frequency-time measures |
| Transthoracic echocardiography (TTE) analysis | Two Time points (1) the day before the race and (2) at 30 min after ending the race | Left and right ventricular and atrial dimensions, and systolic and diastolic ventricular function assessment were collected |
| Change in Body Core Temperature | Time Frame: Continuous measurement was collected from 30 minutes before the race until 2 hours after the end of the race for each swimmer] | Measurement of Body Core Temperature using an ingestible electronic sensor (e-Celsius®, BodyCap , Caen, France) which provide a continuous validated measurement |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Individual characteristics, age | One evaluation assessed the day before the race | The variable collected was the age of participants |
| Body composition, body fat mass | One measurement assessed the day before the race | Fat mass (in kg, % of body mass \[fat mass and body mass were combined to report % of body mass) was measured using bioelectrical impedance analysis (mBCA 525, Seca, Germany). |
| Individual characteristics, training in cold environment | One evaluation assessed the day before the race | The variable collected was the type of specific training in cold environment (yes/no) |
| Body composition, fat-free mass | One measurement assessed the day before the race | Fat-free mass (in kg, % of body mass \[fat-free mass and body mass were combined to report % of body mass) was measured using bioelectrical impedance analysis (mBCA 525, Seca, Germany). |
| Duration | The duration of swimming was collected from the organisers immediately after the race | Duration of the swimming |
| Individual characteristics, gender | One evaluation assessed the day before the race | The variable collected was the gender of participants |
Countries
France
Outcome results
None listed