@article {MierPA2266, author = {Anne Mier and Ghassan Alusi and John Monson}, title = {Increase in maximal expiratory mouth pressures (MEPs) following climbing at altitude on Everest}, volume = {48}, number = {suppl 60}, elocation-id = {PA2266}, year = {2016}, doi = {10.1183/13993003.congress-2016.PA2266}, publisher = {European Respiratory Society}, abstract = {Introduction: It is known that it is difficult to train the expiratory muscles when attempts have been made under laboratory conditions.Aims: We aimed to see whether expiratory muscle strength could be shown to increase as a result of extreme exertion, in a group of normal subjects, after climbing on Everest in hypoxic and cold conditions.Methods: Expiratory muscle strength was assessed by recording maximal expiratory mouth pressures (MEPs) in 5 normal subjects ( 4M, 1F ) aged 26 to 65 yrs ( ht 165-187 cm ) during an exerting climb from below Lukla (altitude 2650 m), to above South Base Camp, over 7 days. Recordings on the last day were carried out after descent to 4950 m from a maximum of 5364 m on that day. Subjects had previously been trained in the MEP manoeuvre before the ascent until reproducible results were obtained. The maximal of 3 measurements was recorded at the same time each evening, after completing each day{\textquoteright}s climb, on arrival in the camp. Oxygen saturations (SaO2) were also recorded daily in each subject. Results on day 1 were compared with those on day 7.Results: There was a significant increase in MEPs in all 5 subjects. Mean on day 1 was 157 cm H2O. Mean on day 7 was 177 cm H2O ( p\<0.05 ). Oxygen saturations fell significantly from a mean of 92\% on day 1 to 83\% on day 7 ( p \<0.05 ).Conclusion: MEPs increased significantly during a 7 day arduous climb on Everest in this group of 5 normal subjects. It is postulated that this was as a result of a training effect on the expiratory muscles.}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/48/suppl_60/PA2266}, eprint = {https://erj.ersjournals.com/content}, journal = {European Respiratory Journal} }