# Creating a rating system for relative footstrike impact on different surfaces

The hardness ratings of tracks are interesting to know, especially as they relate to performances.

But what if we took it a step further, and created a “relative force of impact at footstrike scale” [for lack of a better way of describing it], taking into account not only the hardness of tracks, but of grass, FieldTurf, ashpalt, cinder, and concrete?

Then we take another leap toward real-world accuracy, and take into account the footwear [or lack thereof] associated with the surface. The athlete’s weight and speed might even be factored in reasonably well by some of our statisticians/physicists on the forum, or perhaps simply standardized at a 170 pound athlete travelling 10 metres per second.

For example, we all know Mondo is a lot harder than grass, or FieldTurf. And further, wearing spikes on Mondo provides a much more forceful impact at footstrike than wearing soft running shoes on Mondo.

But is training your star athlete [who has shin splints] better barefoot on FieldTurf or in shoes on grass?

And seriously, do I know how the heck you get forceplates in a guy’s shoes at 10 metres per second without altering the force of the impact itself by the intrusive nature of the equipment? Of course not.

But maybe somebody will figure out a way one day, and make it his thesis! Until then, maybe some estimates from forum members in the following categories would be helpful in program design for athletes prone to impact injuries such as shin splints or achilles tendonitis.

Maybe I’ll start with some combinations and my estimates:

For the purposes of discussion, we’ll have a scale of 1-10, 10 being the hardest possible impact on our hypothetical 170lb athlete running 10 m/s.

Athlete barefoot on soft, dry sand: 1.0

Athlete barefoot on packed wet sand: 3.0

Athlete wearing soft runners on FieldTurf: 3.5

Athlete barefoot on FieldTurf: 4.0

Athlete wearing soft runners on grass: 4.0

Athlete barefoot on grass: 5.0

Athlete with soft runners on rubber track: 6.0

Athlete with spikes on rubber track: 7.5

Athlete with soft runners on Mondo: 7.5

Athlete with spikes on Mondo: 8.5

Athlete with soft runners on concrete: 9.0

Athlete barefoot on concrete!!! : 10.0

Another example: Is spikes on Mondo REALLY less impact than good runners on concrete? Debatable.