Good question...

Sprinting is an an anaerobic exercise... and it is a lot different then jogging... in simple terms anaerobic just means that you are starving your muscles of oxygen... so doing exercises that deprive your muscles of oxygen develops your anaerobic system... and that is the system that you will need to have in boxing...

Now I'm sure there are a lot of people on here who can explain all of this better then I can so if anyone else knows better feel free to correct me...

But anyway... hill sprints build strength, speed... and if your doing it right, it's also going to develop a mental toughness... nothing like being halfway up a steep hill, with every ounce of your body screaming at you to quit but making yourself go on... it starts to build the mental toughness that you need in the ring...

So set goals... write it down... say to yourself, Today I am going to run 15 hill climbs... and then you don't quit until your finished or until you literally can not stand up... and then when you rest for five minutes you get up and do another one... and another one...

The steeper the hill the shorter the length... but think of it like this... most people that are in shape can sprint for 100 yards without slowing down to much... after 100 yards your pace will start to drop... now add in an incline and your distances will decrease...

Hope some of this will help ya... oh yea... how often... well if your in the beginning of building phase/training phase... then every other day won't hurt you... once it's getting closer to your fight you should be concentrating on the technical stuff more... your body should already be in shape at that point...

Blackvenom-2001