In watchos, Can we implement the action when the screen is covered with hand?

In watchos we can back to clock(homescreen) by two way.

1. click dial
2. cover screen with hand

My app record audio with avaudioengine.
But when i try to back to clock by two way written above.
App didn't stay in background, but appear in screen with inactive state.

For example, built-in voice recording app excuted in background when we go back to clock by clicking dial.
And the app also go back to clock when covering screen with hand.

How can i make my app stay in background when dial clicked like built-in recording app.