Mobile fitness app companies RunKeeper and DailyBurn are working to integrate sleep data from personal sleep coach company Zeo into their fitness tracking apps. RunKeeper and DailyBurn are the first apps to take advantage of Zeo's new open API, which enables developers to include a number of sleep-related metrics from Zeo, including total sleep time, amount of deep sleep, amount of REM sleep, number of times awoken, and ZQ (a cumulative measure that combines quality and time asleep for one night of sleep).

“This is an exciting time for consumer sleep education, with Zeo being directly in the intersection of personal health and electronics.” Ben Rubin, CTO and co-founder of Zeo stated in a press release. “Soon, Universities will be able to expand their sleep science research, fitness companies can create sleep fitness applications, and individuals will be empowered with scientifically-based information to take control of their personal wellness. I have no doubt we’ll see truly innovative applications built with Zeo’s API.”

The API will be available to all app developers sometime during the second half of 2010.

Interestingly, the press release notes that IAC recently acquired a majority stake in DailyBurn, which will now be managed by IAC's Mindspark. (The investment/acquisition occurred at the end of last month and no financial details were disclosed.) DailyBurn claims 500,000 members and aims to help them lose weight and gain muscle by tracking every aspect of the food they consume and their workouts. DailyBurn will add ZQ and Total Z to its body metrics tracking, allowing users to better understand the relationship between sleep and their weight loss, according to Zeo.

RunKeeper is a mobile fitness platform for smartphones like iPhone and Android that enables runners and other fitness enthusiasts to track, measure, and improve their fitness.  RunKeeper will track users’ activity and compare against nutrition, weight and now sleep data from Zeo.

For more, check out the Zeo API details here