The combination of cold exposure training and a breathing exercise attenuates the inflammatory response in humans

Abstract

Background - We previously showed that a training intervention encompassing two breathing exercises and exposure to cold enables for voluntary activation of the sympathetic nervous system, reflected by profoundly increased plasma adrenaline levels, and subsequent attenuation of the endotoxin-induced inflammatory response. Herein, we determined the contribution of the different elements of the training, assessed if the training duration is of importance, and whether it can be provided by an independent trainer instead of the well-known individual who devised it. Methods – Forty healthy male volunteers were randomized to either a short or extensive training in both breathing exercises (i.e. cyclic hyperventilation with or without prolonged breath retention) by either the creator of the intervention or an independent trainer. In a subsequent study, 48 healthy male volunteers were randomized to cold exposure training, training in the established optimal breathing exercise, a combination of both, or no training. All 48 subjects were subsequently intravenously challenged with 2 ng/kg lipopolysaccharide to induce endotoxaemia. Results - Both breathing exercises were equally effective in enhancing plasma adrenaline concentrations and this response was also independent from the length of the training or the individual who provided it. Cold exposure training alone did not result in relevant modulation of the endotoxin-induced cytokine response, although flu-like symptoms were markedly reduced compared with the untrained group. Whereas subjects who received training in the breathing exercise alone displayed attenuated plasma levels of pro-inflammatory cytokines IL-6, IL-8, IP-10, MCP-1, MIP-1α, and MIP-1β (-34%, -14%, -48%, -37%, and -28%, respectively) during endotoxemia, combined training resulted in enhanced concentrations of anti-inflammatory IL-10 (+44%) and reduced concentrations of TNF-α, IL-6, IL-8, IP-10, MCP-1, MIP-1α, and MIP-1β (-32%, -35%, -30%, -48%, -29%, -35%, -30%, respectively) compared with untrained individuals. Conclusions - The combination of cold exposure training and a hyperventilation breathing exercise attenuates the in vivo inflammatory response most potently. Our study demonstrates that the immunomodulatory effects of the intervention can be reproduced in a standardized manner, thereby paving the way for clinical trials. Trial registration - Both studies described in this manuscript are registered at www.clinicaltrials.gov (breathing exercises study: NCT02417155; experimental human endotoxaemia study: NCT03240497).

Season Suspension and Summer Extension: Unique Opportunity for Professional Team-Sport Athletes and Support Staff During and Following the COVID-19 Crisis

“…Given that the amount of virus particles reaching the lungs is a determining factor deciding the fate of the athlete (Matricardi et al, 2020), and considering that oral pharyngeal breathing is the predominant mode of breathing during strenuous exercise (Pierson, 1989) while ventilatory rate increases (Pierson, 1989), professional team-sport coaches and support-staff may encourage and (r)emphasize the (re)training of optimal breathing techniques to reduce the amount of viral particles that can penetrate the lungs of their athletes, and in turn, reduce the chance of potentially severe symptoms or complications (e.g., pneumonia). In this regard, the combination of cold exposure training and a hyperventilation breathing exercises (while adhering the required physical distance distance) might be a reasonable strategy to consider given it can help support non-infected athletes' natural defense mechanisms (i.e., promotes attenuation of endotoxin-induced inflammatory responses) (Kox et al, 2020).…”