The Effect of Cold Showering on Health and Work: A Randomized Controlled Trial.

Geert A Buijze,Monique H W Frings-Dresen,Marcel G Dijkgraaf,Bas C J M Van Der Heijden,Inger N Sierevelt,Jacobus Van Wouwe

doi:10.1371/journal.pone.0161749

Geert A Buijze, Monique H W Frings-Dresen + Show 4 more

Open Access

https://doi.org/10.1371/journal.pone.0161749

Copy DOI

Abstract

PurposeThe aim of this study was to determine the cumulative effect of a routine (hot-to-) cold shower on sickness, quality of life and work productivity.MethodsBetween January and March 2015, 3018 participants between 18 and 65 years without severe comorbidity and no routine experience of cold showering were randomized (1:1:1:1) to a (hot-to-) cold shower for 30, 60, 90 seconds or a control group during 30 consecutive days followed by 60 days of showering cold at their own discretion for the intervention groups. The primary outcome was illness days and related sickness absence from work. Secondary outcomes were quality of life, work productivity, anxiety, thermal sensation and adverse reactions.Results79% of participants in the interventions groups completed the 30 consecutive days protocol. A negative binomial regression model showed a 29% reduction in sickness absence for (hot-to-) cold shower regimen compared to the control group (incident rate ratio: 0.71, P = 0.003). For illness days there was no significant group effect. No related serious advents events were reported.ConclusionA routine (hot-to-) cold shower resulted in a statistical reduction of self-reported sickness absence but not illness days in adults without severe comorbidity.Trial RegistrationNetherlands National Trial Register NTR5183

Highlights

Cold bathing is a common custom in many parts of the world
A negative binomial regression model showed a 29% reduction in sickness absence for cold shower regimen compared to the control group
A routine cold shower resulted in a statistical reduction of self-reported sickness absence but not illness days in adults without severe comorbidity

Summary

Introduction

Cold bathing is a common custom in many parts of the world. Ever since the introduction of civilized bathing, humans have experimented with water temperature variation to expose the body to extreme conditions. Cold bathing has been claimed to have multiple beneficial effects on health such as improvement of the immune system, cardiovascular circulation and vitality, but any true association remains unclear.[2] Previous investigations on the short-term effects of cold exposure have shown increases of cortisol and norepinephrine concentrations with modulation of the physiological response but showed minimal or no immune modulation.[3,4,5,6,7] the cumulative clinical effect and relevance for health after adaption of cold exposure (response conditioning) in healthy humans remain speculative as randomized controlled trials are lacking

Objectives

Methods

Findings

Conclusion