What GA said. When you're older you're supposed to be using your experience to your advantag. If you're getting beaten in sprints then you need to use some different tactics. It's hard to win from the front especially if you've been pulling.

Being older also means that you need to train differently. You won't recover as well as when you were younger, and you need to do more intensity. I also find that I need to do weight and core work to keep some amount of basic strength. If I just ride and don't do anything else then I get weak.