Keeping another app (e.g. Maps) on top of Health?

So when I'm taking a stroll to explore I start an exercise (walking), but sometimes I need Google maps up so I can navigate. Once the exercise is started, I can manually go back Home and start maps, but the Health tile keeps coming to the front and I have no easy way to switch back to maps without first going back to home.

Anyway to keep maps (or any other application) on top while also having Health running to keep track of my exercise?