It’s from a article at the time he ran his 19.58.
“I haven’t done any speed-work yet, but the 400s I did earlier showed my fitness.”
Asked what he meant by “no speed-work”, Gay explained, “Speed-work in practice is maybe 60m fast, 30m fast, running and running and running.”
“I haven’t really touched it yet. I may have done a couple 60ms in practice, and some starts, that’s considered speed-work, but I haven’t really turned my body on. I’ve been doing 400m and longer distances.”