Yes you can.

First, download the KrowdFit app from the App Store and sign in, from the Trackers page (Profile > Settings (gear icon) > Trackers > Add a Tracker) select Enable Apple Health from the top of the screen. This will prompt the permission access screen for Apple Health, grant all permissions and allow. Your Apple Health data will start to flow into KrowdFit. 

If this is your first time using the app the enable Apple Health will be part of the sign up experience.