You can safely update the Joomla 3.4.5 to Joomla 3.4.7 via Joomla Update Dashboard (ROOT/administrator/index.php?option=com_installer&view=update)
But never ever update the T3 framework. Because SportMart uses a highly customized T3, you will lose all the SportMart styles if you update it.
Currently there is no further update for SportMart. You are up-to-date. Check our Facebook page or visit our website once a month or every other week to be notified when a new version of SportMArt is released.
Regards.