I read about this movement as a solution to shin splints over 25 years ago, and had to search the web for a good description. From http://tt.tennis-warehouse.com/showthread.php?t=284684
(for a full look at the topic) I found this:
I had shin splints once--no fun. The way I got rid of them was to go to the gym and use a leg curl machine in reverse. Usually on a leg curl machine you lay face down on your stomach and hook your heels under the pads and curl the weight up to your butt working your hamstrings. Instead, sit on the machine facing the other way and hook your toes under the pads and just flex your ankles toward you which works the muscles of the shins. Start with the lowest weight and go for many reps. It has now been several years and I have had no problems since (I play at least once nearly every day, usually twice, on all surfaces) and have some amazing anterior tibialis muscles to show for it.
Hope that helps.