Index: src/bp-members/bp-members-loader.php
===================================================================
--- src/bp-members/bp-members-loader.php
+++ src/bp-members/bp-members-loader.php
@@ -287,6 +287,7 @@
 
 		// Global groups
 		wp_cache_add_global_groups( array(
+			'bp_last_activity',
 			'bp_member_type'
 		) );