My understanding is that they hook a runner up to a machine that measures their oxygen consumption, have them run a given pace in a given shoe, and measure how

My understanding is that they hook a runner up to a machine that measures their oxygen consumption, have them run a given pace in a given shoe, and measure how much oxygen they consume as a proxy to how much energy they’re using. With the super shoes, they use less oxygen to run at a given pace Example abstract: https://pubmed.ncbi.nlm.nih.gov/30374945/ https://pubmed.ncbi.nlm.nih.gov/30374945/