How to prevent sore muscles from exercising?

So now that summer has started, I'm doing a workout class every morning that's with a personal trainer and it's for the female athletes at out school and it's like a strength training/agility class. And the guy pushes us hard. The workouts are insane. So that's every morning, which makes me super sore. Then on top of that, every Monday and wednesday I have the workout class, then high school soccer practice, and right after club practice. And I'm sooooo sore. How can I keep my muscles from getting this sore? I'm 16. Btw. If that helps at all