Static stretching is mostly a waste of time, the research does not support it in any significant way. Rather dynamic stretching intermixed with other movements gets the body fully warm before practice and games. Found a perfect article for this post, includes a video showing a 15-20 min warm-up that covers a general movement/dynamic stretching warm-up:

http://www.youthfitnessmag.com/warm-up

you could have them run, throw, catch, work on the basics, and stretch

stretch to prevent from pulling anything and do ur basic warm ups such as pitching back and forth,batting, and have your coach hit a ball so that you can try to catch it

There's a lot of warm-up exercises out there. You can use some kind of rubber cord to warm your body up - the best thing is it's portable and you can adjust the intensity level.

Before every game, I would spend some time on the foam roller getting all my muscles loose.

Your priority when warming up should be the whole body and not just the throwing shoulder. Legs and hips provide most of your power in sport so make sure to get the hip joints strong and mobile. Maybe some easy lunges focusing on hips and glute areas followed by a cord warm up for the shoulder can be a good start. Then make sure you do some dynamic stuff like jogs forward and backward. It's basic, but it'll get you started.

good luck.

swing two bats together so when you are up to bat... it is wayyyyyyyyyyyy easier to swing!!

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