Wow! This is an interesting topic in sprinting. Getting out of the blocks is very important.
Just as important as you getting in the blocks. At track adiktz we've seen a lot starting block positions.
You've heard about shin angels, hip height, pad and arm placement but not so much about foot placement. Here we're going to focus on where it all starts.
First, Place your pads appropriately (see pad placement article).
Feet in pads:
Second, Place your feet in the pads. Be sure to firmly place the balls of your feet in the pads. Rear foot first front foot second.
As you settle into the "on your marks" position you'll feel your feet firmly planted against the pads.
Here is where it gets tricky some athletes place their toes on the ground while the balls of their feet are flexed pressing into the pads. Other athletes place their foot in the pad with toes not touching the ground (i.e. the top edge of their toe aligned with the edge of the pad)
Our advice here is to use which ever method is most comfortable for the athlete based on the flexibility of their Achilles and ankle.
Keeping in mind the goal of having the athletes heal flexed and pressings against the full surface of the pads, no empty space when the athletes come to set.