you may have access to the servers php.ini file ask your host.
many hosts allow you to create an ini file to change certain parameters an out it in the root of your site.
However, that's not I'm referring to. the code I provided can be added at line 1 of each of the admin pages to extend the session time out, you may want to change the value 1440:
to something else like 3600 (1 hour):