Originally Posted by jonestim
What other fitness do you do during the week? You need to get stronger.
It's not just about staying active throughout a week to get your body in shape. Yes, working out and exercising will get your body in shape, but it won't be in "game shape".
It's very hard to mimic the explosive and repetitive movements/strains that happen in a tennis match (or any other competitive sport for that matter). All I can say is you've got to log in more court time. I can play back-to-back-to-back-etc. days and my body won't really feel anything, but I'm exhausted after a game of full-court basketball. That's because although I'm in shape, I'm not in basketball shape.
If you want to feel alright after playing a 2.5hours 3setter, you've got to be able to log in at least 10 hours a week.