From what I recall tubing has some of the same possible complications. Also the resistance isn't really where you want it I think. I'll use a curl as an easier example.

When doing a curl the resistance starts from less to more finishing at the top. When lifting an object in a real life situation the most resistance is in the middle when the arm is bent 90 degrees.

In a punch the resistance band leaves gives the most resistance at the end of the punch. The body will be working hard to be pushing extra then. Like mentioned above , stopping the punch, so as not to hurt the elbow joint would naturally be facilitated by the band.

Again, the body also learns by doing. They have gotten results with runners and swimmers by pulling them just a hair faster than they can go on there own and it teaches the body to go faster. The band is teaching it to move slower.

I think one might almost get more out of a band pulling the punch a bit.

Now strength conditioning and sport training can blend in that you work one way and make sure you teach the muscles another way too.

However I would think pushing type exercises using heavy weights and low reps with movements that incorporate pushing and twisting and sometimes lunging might be best.

One example is laying with your back on a swiss ball, feet on ground. Arms, bent at elbows out horizontal to the sides. A dumbbell in one hand. You twist as you push straight up, keeping shoulders retracted and pushing down onto ball with other arm. You end up on one elbow on the ball with the other arm fully extended straight into the air. More advanced versions have you have on the ball with dumbbell elbow about on the ground and you push and twist all the way up ontop the ball on your other elbow.

not able to find a clip
http://www.youtube.com/watch?v=I4Cng303IIY
thats a one arm swiss ball press (ignore tempo and reps)

The one I am talking about leaves the body almost sideways with bottom elbow only thing touching ball with other arm straight up in the air fully extended.


The body learns by doing...
Just like reading where we recall best the first and last bit of a chapter or paragraph so the body learns best from the first and last parts of training or a round.

Most people train fatigued and teach the body to be fatigued. Of course there is a balance and there are benefits to pushing the body - those should be, in my opinion, conditioning days... anything close to punching (of course there is periodization) should be fast, explosive and always finish strong. Daily getting tired and sloppy and slow teaches the body to do just that.

Say for some conditioning exercises close to fight... you would want to stop as soon as you start to slow at all.

Like how the Thais kick the back over and over... I would do untill my speed or form dropped and take a break before doing more. Over time build up endurance. Starting always with power and speed and technique and build duration. Instead of long duration with poor speed, power and technique.

Body learns by doing... They take experienced runners, hook them up to a heart rate monitor and with in a couple steps the heart is right up there working very hard... It is conditioned to know running is hard and works hard when it doesn't even need to yet...

Same with the anything... what you do in training is what you teach your body to do... I think punching the bag is probably best for training punching... supplementing with conditioning NOT every day.

I bet if you had a band, little resistance to start (like half an inch) then no resistance. Train the explosiveness (just a little resistance and focus on BANG! and all forward... bet that could have some benefits...