HOTWORX offers workouts in infrared saunas. From yoga and Pilates to HIIT workouts, the classes are done in temperatures up to 130 degrees. According to Kayla Grudzielanek, instead of heating the air with steam, like a traditional sauna, infrared creates a dry heat similar to the warmth of the sun and without UV rays. The infrared heat gives you the same results as a regular workout but quicker. Infrared sauna workouts are between 15 and 30 minutes each.