I got a new book to help me strengthen my core. The workout above is from their website. I like the layout of the book and their philosophy. The exercises are explained well and organised sensibly. The website offers video demonstrations. I find the website easy to use.
The book provides descriptions of the movements that I find easy to follow, even when I am down on the floor. The sections of the book are colour-coded to show you the relationship of the movements to their purpose. The book includes lots of full colour photographs and coaching tips. So far so good!