When I was in college some called them Thunderwear but there was no technology involved IIRC.Phew, thank goodness for that, I'm not interested in my earbuds providing me fitness information all I care about is sound quality so I can safely save some money, not upgrade, and not feel like I'm missing out.
Also is it just me or is saying "your headphones will provide fitness information" like saying "your underpants will tell you the weather forecast", normally those two things are not related.
p.s. weather predicting underwear copyright 2021 MJaP (just in case... well you never know...)