According to the Agile philosophy, it is important for the team to work together as one to achieve the goal fixed at the begenning of an iteration. With that in mind, I know that developpers and analysts can help the QA at the end of an iteration to make sure all the testing is completed in time.
How can the QA help the team at the begenning of a sprint if no Stories are completed and that test plans are ready.
(We are team of 5-6 people with 1 QA and we are on 3 Weeks sprints so the dead time can be long for the QA)