Basically, I've had pretty crappy form for most of my running career (major heelstrike), and for the past couple of months I've been working on being able to strike mid-foot/toes. At this point, I can land mid-foot for the duration of an 800, but after that my calves aren't strong enough to hold me up and I'm forced to land on my heels.
I'm planning on incorporating some barefoot running this summer to help with strengthening. What else can I do to supplement this?