The DART is an excellent exercise for strengthening your whole back line and is really safe.
I’m a sucker for a Geordie accent so have used this teacher again because I particularly like how she shows you the safest version and discusses core activation, just like we do in class. My only additional comment about this movement is to add the rolling together of the legs to feel the engagement of your adductor (inner thigh) muscles. This helps you to find your pelvic floor which in turn helps you to engage your core more effectively. Keep your feet connected to the ground for added stability.
Start the movement by engaging the legs first, aiming to simultaneously engage the legs as the upper body lifts, feeling the opposition as you lengthen the crown of the head away from the feet.
Do the movement on your exhale (out breath) because this will help you control how much core you use. Holding for a long inhale will add a bit of weight training before you exhale to return to your start position.
Once you’re happy with your technique you can start adding strengthening variations, making sure you keep your shoulders from creeping up to your ears :
Floating arms – Whilst you’re up in your Dart, on your exhale float your arms out to the side in line with your shoulders (T shape), palms will face down towards the floor, hold as you inhale and return back to your start position on your next exhale. If this is ok next time you’re up there let the arms pass through the T position lengthening them forward, hold and return as before and repeat. Be careful is feels quite loaded.