Running heal strike or toe strike

I think too many people worry about which part of their foot hits the ground first, and that instead they should just make sure it lands under their center of gravity instead of in front of it.

x2 ......believe me, if you start drastically modifying your gait patterns you are opening a "can of Whoop A$$" on you lower extremity...do whats natural for you...

with that said i am a heel striker unless i am sprinting

Heel, forefoot, or midfoot is more a byproduct of the rest of the stride, and shouldn't really be something you strive for on its own. I just wrote up a piece on my blog about it: http://welcome-to-briders-place.blogspot.com/2011/03/i-am-not-role-model.html Pretty much sums up what's been said here.

I don't know what a heal striker is, but I was a heel striker. Is a heal striker a person with natural regenerative abilities?

More to the point of the OP. The goal isn't so much to eliminate a heel strike, it's to eliminate overstriding. Part of that process can involve drills where a person will land on their forefoot, as that makes it very difficult to overstride. Once you get to the point where your feet are landing closer to under you as opposed to way out in front of you, it doesn't matter what part actually strikes first.

Be aware that this process can take 4-12 months depending on how much you run and how quickly your muscles/tendons/ligaments, etc. adapt. It's also a process you need to commit to entirely. Going back and forth between the techniques can be a recipe for problems. It may not yield any immediate gains in speed either. That will come as a result of being able to run more.

As a heel striker I was not able to run much more than 20 miles/week without experiencing debilitating pain. I made the switch 8 years ago and last year averaged just over 60 miles/week for the entire year. All with no pain. I run every day as well and haven't missed a day in almost 5 months.

There are lots of shoe options available now to help with the process. The Merrell Trail Glove, Newtons or VFF are prime examples. Shoes with big clunky heels and large heel to toe drops make the process more difficult.

Take it slow, be consistent, and be prepared to deal with some pain in the calves and likely the achilles until you adapt. You will likely blow off doing well in races this year, but long term this could be a benefit toward a rewarding running career.