So many horror movies have been described as “pulse-pounding” over the years that the words have virtually lost all meaning. But A24, the company behind the upcoming horror flick Hereditary, is looking to back up its claims by actually testing the heart rates of audience members during the film.

During select screenings of Hereditary, the company had viewers record their pulse rates and share the results with the company by wearing an Apple Watch while in their seats. A graph showing some of the challenge's results from recent screenings revealed spikes as high as 130, 140, 157, and 164 BPM during key points in the movie, which is a mammoth leap from the 60 to 100 BPM that would be considered normal for an adult. A promotional video for the challenge found on Mashable even shows one audience member’s resting pulse rate going from 63 BPM all the way to 130 during one of the film’s scarier moments.

It's another interesting cog in Hereditary's marketing machine that already includes its own Etsy shop revolving around the movie's creepy child main character, Charlie. For horror buffs, the challenge can be seen as a modern version of the types of gimmicks director William Castle helped introduce to the genre decades ago, including a "Fright Insurance" policy that would pay $1000 to your loved ones if you died of fright during his films.

Hereditary is being hailed as one of the more genuinely frightening horror movies in recent memory, so even if A24’s heart rate challenge is just another marketing stunt, the end result should be enough to satisfy fans of the genre. While certain screenings had prizes for the first 10 people in line who participated in the challenge, anyone can monitor their pulse rates if you have an Apple Watch with the Health app installed when the movie opens on June 8.