Flushed neck

This exercise can be a bit of a strain if you have back problems, so exercise caution and stop if you feel any discomfort or pain.

Plank Hop

Stay on your stomach and place the circle between your ankles. Squeeze your inner thighs to hold on to it, and rest your head on your hands. Engage your core, squeeze in on the circle, and lift your knees off the floor using your hamstrings and glutes, making sure not to engage your back. Think length, not height, and don't let the circle fall out from between your ankles.

The swan-dive