Running Economy at Submaximal Speeds

The context of all of this is three kilometer performance and running economy at submaximal speeds. We confirmed our long known that adding 100 grams per shoe worsens your running economy about 1%. Now interestingly enough people didn't run 1% slower but it took a couple of years for us to fully realize that it actually made sense. So there's something with the relationship between energy and velocity and air resistance and things like that, overall sort of we do see that there is an effect.