My coaching of indoor cycling classes started in 1997/98. The first place I worked at was AFC Sportz in Boston. Every health-club at the time had a tape and cd player. It wasn’t easy to burn cds at the time, so most group exercise instructors and coaches made mixed tapes. You put the little finger in the tape reel, turn, and cue it up. Then you put it in the dual deck recorder and push “pause/Record.” You had to make sure the music source was cued right, and you were ready to start making a mix.
Too many tapes got worn out, gnarly, or crushed. It was very sad when one died because you had to re-record the entire thing.