"In Rochester, Minn., Jeremy Scherer and his wife spent three hours playing tennis and bowling, two of the games included with the Wii. Mr. Scherer says he managed to improve his scores — at the cost of shoulders and back that were still aching the next day. 'I was using muscles I hadn't used in a while,' says Mr. Scherer, a computer programmer who describes himself as 'not very active.' Mr. Scherer is vowing nightly 'Wii workouts' to get in better shape."