How do I get back in shape for baseball?

Lots of tee work will fix your swing, but only if you use correct form. Really focus on your arm extention. For getting in shape, there is a great program that will get you in shape fast. Anyone can do it. Professionals use this program. Monday will be long sprints. Sprint foul pole to foul pole and then a quarter way back, then walk the rest of the way back to your starting point. Do that at least twice. Next, Sprint pole to pole, walk three quarters of the way back and then sprint the last quarter. Tuesday is short sprints. This all happens from foul pole to foul pole. Sprint a quarter of the way, walk a quarter, sprint a quarter, walk a quarter, and then the same back. Do that 2 or three times. Wednesday is agility day. Use little speed hurdles and taller speed hurdles to step in between and them sprint out 10 yards. Repeat 2 times on taller and shorter speed hurdles. You can also use an agility ladder if you want. Just sprint out 10 yards after each one. Thursday is recovery day. Just a mild jog will do. Friday is mile day. Test out the program by running the mile. See if you improve after 1 week, 2 weeks, 3 weeks, and so on. You will be in great shape if you stick to this program. To work out your deltoids, take a 5 pound weight in each of your hands and bring out your hands straight in front of you 180 degrees until they are over your head while keeping your arms straight. Next bring out your hands out to the side and keep them straight until they are over your head. Repeat. I'm sorry if the deltoid workout explanation was a little vague but it is hard to explain. The main thing about this answer is that you stick to the running program and you will be in the best shape of your life. Good luck with baseball!