You can use this feature to run the Update Statistics command. When SMS creates database indexes, SQL Server creates a set of statistics about the data that is contained in the index. When you run a query, the SQL Server Query Optimizer uses statistics to determine the most efficient way to execute the query. Over time, the initial statistics created with the index become out of date. The Update Statistics task rebuilds the statistics and enables the optimizer to run more efficiently.
Note SMS automatically updates statistics, which is set at a predetermined schedule and is not affected by this task setting.
Schedule a Database Maintenance Task
Maintaining a Site Database Overview