Treadmill for boxing competition training?

In addition to my 3 days a week weight training sessions (m,w,f) and my 5 days a week boxing training sessions (m-f), is it ok if I do 3 days a week (tues,thurs,sat) of running on the treadmill? I plan on running for 20 minutes at a time. I will gradually try to increase the pace each session, starting at 6 mph. In a couple of weeks maybe I'll work up to 7 mph. Tues and thurs I will do this right after my boxing training and saturday I will do this in the morning. My goal is to get into boxing shape for a competition in November.

I used to train in Kyo Kushin karate and TKD and see no problem why you shouldnt train that way.

Just listen to your body and if you feel tired lay off a bit.

I used to go to tkd 3 times a week and run for 30 minutes 5 times a week plus weight training and cardio stairmaster, or has you wanna do treadmill.

Note would be better to run in the street, running on a treadmill is just not the same.

Is 20 minutes enough or should I bump it up to 30 minutes?

Anyone?

20 is good when you do it after weigh training or boxing...but when you do it by it self go for atleast 30.
and it shouldnt be a problem at all..i know boxing can get you out of breath really fast..so all this cardio training should make your stronger on you cardiovascular side.