Well you have Athos clothing trackers coming out soon, which tracks muscle exertion.
Thing is although, it costs $300-$400 dollars. Runkeeper works with the phone you already have, and you can optionally add a couple of $50-$150 accessories. Very different price points.
I remember an Under Armor commercial demoing some sort of envisioned prototype of this kind of tech.
edit: They also have something called Armor39, a strap that goes around your chest. I am now curious. Anyone used this?