Im working on some of the sources CF but I have heard more from PT and CPTs in the recent past about which core exercises are relevant to sprinters. When I locate one that I’ve read I will share.
I too questioned the relevance of planks. I have found greater success with “supermans”. (thats when you lie on your stomach, spread arms and feet up and apart and balance for 20-30secs. It does seem that planks work the glutes a bit more tho.
Let me also apologize to you guys for referencing a source without giving the source. That was a bit amateur of me:o