thatgaytrainer began creating 30 minute high intensity interval training (HIIT) classes while an independent contractor at Village Gym in La Mesa in 2012. After going independent, the class evolved into "Afterburn," a metabolic interval training class complete with  warmup, core work, strength training, interval training, cool-down, and stretching. In its final iteration, "Afterburn" was the only heart-rate monitored outdoor class complete with real-time display in San Diego before finally being discontinued during the second COVID shut down in San Diego in December, 2020. After a successful 8 year run, there are currently no plans to revive the class.