NT Prone Hold
Abdominal and Core Strength (Prone Bridge Hold)
The information presented here is not designed to substitute professional medical advice. Consult a doctor before starting any physical activity or training program and seek medical advice if you feel pain during a training session.
Basically, you lie on the floor face down supported by your toes and forearms. This picture indicates the correct position. (Update: the difference from this photo is that you now have to have your PALMS flat on the ground - not in a fist)

You must hold this position as long as you can. Whilst there is no minimum standard, we note that other state police services that use this test - such as Victoria - require a minimum of 60 seconds hold.
Your final time will be recorded when you move your arms or feet OR if you raise or lower your body out of the straight bridge position.
So when you practice this, get someone to watch you, or use your phone camera to video yourself and make sure that your feet DO NOT MOVE and that you're keeping your body straight.