Tuning of Reports in Sql Server

I have a report using 4 matrices and 3 stored procedures to populate those matrices.The stored porcs while executing through the sql server management studio dont take much time. But when i execute the report, it takes around 5+ minute to execute.

Any suggestions why is it happening and how can i improve the report's performance.

The difference in performance can be (assuming if stored procedures are run with same set of parameters) due to difference in execution plans triggered due to different connection settings.
To understand if there is different execution plan
run profiler with monitoring objects Performance, TSQL, Stored Procedures etc with all columns included for both runs with Reporting Services and Query Analyzer.