I am always on the speed bag doing what should be done however I am wondering if someone can break it down exactly what is improving. I know "speed" but can someone break it down a little better.

hand-eye coordination and timing

you are not improving, if after 3 3-minute rounds of the speedbag, your shoulders are not tense

you are not improving, if after 3 3-minute rounds of the speedbag, your shoulders are not tense
I do five or six and my shoulders want to fall off. I am improving for sure, just wanted some more technical terms thrown out as opposed to just "speed."

tx

What kind of combinations are you doing? Are you doing traditional boxing triplet rythm or doing front and back stikes? You may want to check out Alan Kahns website speedbag central for some other combinations you can find it here http://www.speedbagcentral.com/ Alan also has a Speedbag forum you can ask some folks much better than me. I would also say if your endurance is improving you are definatly improving. I usually do 12 three minute rounds on the speedbag working on endurance and technique. Hope this helps

sometimes i will have some one count how many times i hit the bag in one round, then try and beat it.

once again great feedback thank you guys...