The Effects of Cold Water Immersion With Different Dosages (Duration and Temperature Variations) on Heart Rate Variability Post-exercise Recovery

Study Overview
=================
Brief Summary
-----------------
The aim of the present study was to investigate the effects of cold water immersion (CWI) during post-exercise recovery with different durations and temperatures on heart rate variability (HRV) indices. 100 participants performed a protocol of jumps and a Wingate test, and immediately afterwards were immersed in cold water, according to the characteristics of each group (CG: control; G1: 5' at 9±1°C; G2: 5' at 14±1°C; G3: 15' at 9±1°C; G4: 15' at 14±1°C). Analyses were performed at baseline, during the recuperative technique (TRec) by CWI and 20, 30, 40, 50 and 60 minutes post-exercise. The HRV indices average of all RR intervals in each analysis period (Mean RR), standard deviation of normal R-R intervals (SDNN), square root of the mean of the sum of the squares of differences between adjacent R-R intervals (RMSSD), spectral components of very low frequency (VLF), low frequency (LF) and high frequency (HF), scatter of points perpendicular to the line of identity of the Poincaré Plot (SD1) and scatter points along the line of identity (SD2) were assessed. Comparisons between groups and moments were performed using the technique of analysis of variance for repeated measures in two scheme factors. A significance level of p<0.05 was considered.

Official Title
-----------------
The Effects of Cold Water Immersion With Different Dosages (Duration and Temperature Variations) on Heart Rate Variability Post-exercise Recovery

Conditions
-----------------
Cryotherapy Effect

Intervention / Treatment
-----------------
* Other: immersion cold water


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: male sex healthy aged between 18 and 30 years classified as physically active through the International Physical Activity Questionnaire Exclusion Criteria: smokers alcoholics use drugs that influenced cardiac autonomic activity cardiovascular, metabolic or endocrine diseases.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
-----------------
Male

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: GC<br>Control group - CG (n = 20), which suffered no recuperative technique | |
| Experimental: G1<br>G1 (n = 20) was subjected to a recovery procedure by immersion cold water for 5 minutes as from 9±1 degrees Celsius | Other: immersion cold water<br>* immersion cold water at different temperatures and exposure times<br>|
| Experimental: G2<br>G2 (n = 20) was subjected to a recovery procedure by immersion cold water for 5 minutes as from 14±1 degrees Celsius | Other: immersion cold water<br>* immersion cold water at different temperatures and exposure times<br>|
| Experimental: G3<br>G3 (n = 20) was subjected to a recovery procedure by immersion cold water for 15 minutes as from 9±1 degrees Celsius | Other: immersion cold water<br>* immersion cold water at different temperatures and exposure times<br>|
| Experimental: G4<br>G4 (n = 20) was subjected to a recovery procedure by immersion cold water for 15 minutes as from 14±1 degrees Celsius | Other: immersion cold water<br>* immersion cold water at different temperatures and exposure times<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline in indices of heart rate variability at 60 minutes |  | 20, 30, 40, 50 and 60 minutes post-exercise | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Recovery of function, Autonomic nervous system, Heart rate variability, Cryotherapy, Immersion