I'd advice some boxing drills.
They're at the most without gym equipment and produce results!
This dude here is all about natural exercises, you can take a look in his videos!!
warning, don be nuts as this guys, at the end, he has years of hardcore training, you dont have to do 20 explosive push ups,
start with 2x10sets(in addition to your regular workout)
2 x week,(do tuesday then skip two to three days and do again)
on the third and fourth week, goes to 4x10 twice a week,
then the next two weeks go for 2x8 with 1minute resting, then 5x5 reps with 30secs in between.
You dont do like this he 's doing in this vid, just clap your hands once as u push yourself off the floor, do it without stopping and fast, and do have to touch the floor with chest.
Honestly, developing explosion without hurting your shoulders takes time, so do it in time, at the end, a hurt fighter isn't different from a hurt cow
