How hard do you throw in the bullpen?

I am just getting back to pitching and wanted to know how people handle bullpen throwing, both on game day and between starts.

I have found that even after a couple days rest if I throw more than 75% I still have a bit of arm soreness.

Also, warming up for a game, is there any point to throwing 100% until you are actually throwing to a live batter? What about warm ups for each inning? What is your philosophy on this?

In the pen, start off slow, nice and easy. Your last couple of pitches should be 100%, I would toss in a fastball as your final pitch just so that you are all the way there.

As far as recovery, you are not going to get back to 100% between appearances. But the key is get yourself in shape physically and make sure your power is coming from your legs.

Btw, I haven't pitched in fifteen years, but nevertheless I think this is solid advice.