Before the Apple Watch was officially announced, there were a lot of rumors surrounding the device which said that it would have a lot of emphasis on health. The actual product did not come with all the rumored features but there are still a ton of health-related features and functionality all the same.

That being said have you ever wondered how Apple goes about testing the device? The folks at ABC News recently revealed the secretive Apple Watch testing facility as part of their Good Morning America segment. Basically the video above shows how Apple goes about testing the device and some of its health features.

For example it shows users wearing masks that measures the change in breathing amongst other statistics. The users were also put through the paces and participated in a variety of workout regimens that includes rowing, yoga, and running. Now you would think that these people knew what they were testing, but as it turns out they didn’t.

According to Jeff Williams, Apple’s SVP of operations, “[The employees] knew they were testing something, but they didn’t know it was for the Apple Watch. We hooked them up with all the masks and so forth, but we would put on an Apple Watch covered up.” Apple also went to the extremes by taking the Apple Watch to places like Alaska and Dubai to see how the wearable would fare in such conditions (hot and cold).

If you’d like to learn more about Apple’s testing methods, check out the video above for the details. However it is only a preview for a larger piece which is scheduled to air tonight at Nightline 12:35AM EST.

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