These are competitors you may recognize, too. On top of athletes from Sierra Leone (sprinter Hafsatu Kamara) and Trinidad & Tobago (hurdler Mikel Thomas), three of them are US medal-winners: 4 x 400m relayer Natasha Hastings, relay sprinter Mike Rogers and 400m hurdler Michael Tinsley.

This is as much marketing for the Halo Sport's fall launch as anything else, so there's good reason to be skeptical (especially given the $649 pre-order price). However, you can look at this as a grand experiment that goes beyond Halo's existing partnerships. If the athletes training with these headphones come home from Rio with medals, it'll suggest that this brain-changing headgear can produce quantifiable results.