A new study out of the University of North Carolina in Chapel Hill is making a claim that is sure to surprise many people who go to the gym regularly: their workouts may actually be having a negative effect on their libido. While it’s true high testosterone levels caused by working out can increase the sex drive of a man, the study found that working out too much can actually lower your sex drive.

The study was based on surveying men about their workout routines and their sex lives, and the researchers were surprised to find that those who worked out harder and more often were more likely to have a lower libido. Scientists asked respondents about their workout routine, their sex life and their general health and wellness.

They then organized the respondents according to their answers, grouping them by both their lbido and their intensity of workouts. Those with the longest and most strenuous workouts were more likely to be in the low to moderate libido group.