Barrett, you need to get into the pool with a kick board and work your hips. Then, before you return to racing, you (eventually) need to work on short sprints up a steep hill to help the muscle respond to quick firing. Focus on picking your knees up when you do this later. In the meantime, focus on kickboard and also walk backwards on a treadmill up a 10% slope at 2.5 mph for 30 minutes. A little stretching will help too. Good luck!
