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0 Responses22 Feb 2015
15:38 GMT
Most RecentIn exercising, I regularly go up and down a flight of stairs holding my breath until it becomes uncomfortable. Posted by Caleb3 on 22 Feb 2015 at 15:38 GMT -
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Most RecentMedia Coverage of This Article Posted by PLOS_ONE_Group on 14 Dec 2012 at 22:19 GMT -
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22:48 GMT
Most RecentI will respond Posted by Jeff_FDunn on 02 Oct 2012 at 22:48 GMT