The Knee Switch is a fantastic lower body mobility drill. It teaches you to open up your hips and ankles with more advanced variants training movement from the ground to standing - an essential for martial arts and even more important for people advancing in years

The key points of the drill are:

Keep the upper body neutral and upright.
Initiate the movement from the waist
Don't hold your breath; allow your breathing tempo to be governed by your movement

Have fun with this - will demo advanced variants after I've burnt off the mince pies!