Keeping session alive via webservice

Hi Guys,
 
I was wondering if updating a session value from within a webmethod call made from jquery would be able to keep my session alive?
JS:
$.ajax({
            type: "POST",
            url: "MyWebService.asmx/Keepalive",
            async: true,
            contentType: "application/json; charset=utf-8",
            dataType: "json",
           });
VB:
<WebMethod()> _
    Public Function Keepalive() As Object
           Session("Keepa ...