Don't let the KB swing above your head. Need to keep the lats engaged to safeguard your back. Swing the bell too high and you lose stability. No bueno.
If your back is buggered up from the KB swings the other day, drop KB jacks altogether, or just swing them.
Not getting enough out of those burpees? Try them one legged. Just the kick out part should be one legged. Once your feet come back to the middle land on both feet and initiate the jump phase with both feet.
Twisting good mornings work best with both hands on the DB. Ashley is demoing a great one-armed version. It's the beginner version.
Don't lock your legs straight on the good mornings. Bend the knees slightly, then lock them. Don't squat through the knees. All the bending should be done at the hips. This will ensure max hammy soreness! :)
Es no bueno to move your feet, knees and hips during the cross-body pulldowns. Initiate all the movement through your core. Lock your hips forward and do all the twisting with your abs. Yes, your arms/shoulders will move for sure, but NO HIPS. If your feet are moving, you are doing it wrong.