Feb. 25 (UPI) -- Higher testosterone levels can boost the male sex drive, and exercise has been shown to raise testosterone levels. But new research suggests too much working out can have a negative effect on the male libido.
When scientists at the University of North Carolina in Chapel Hill surveyed men about their workout routines and sex lives, they found men who engaged in frequent and strenuous exercise were more likely to have low libidos.
The study included three separate questionnaires: one featured intimate questions about the respondents sex life, another featured inquiries about the respondent's weekly workout routine, and a third featured general health and wellness questions.
All respondents were volunteers and many were current or former endurance athletes -- runners and cyclists.
Researchers organized the respondents into groups based on their answers. Exercisers were organized by the length and intensity of their workouts. Additionally, men were grouped based on the strength of their libido.
Men who reported engaging in long and strenuous workouts were more likely to be found in the low to moderate libido group.
Researchers published their study results in the journal Medicine & Science in Sports & Exercise.
Study leader Anthony Hackney, a professor of exercise physiology and nutrition at UNC, told the New York Times, their work doesn't prove high intensity workouts cause a diminished sex drive, only that strenuous exercise "was associated with lower libido."
But the research also showed, as previous studies have, that light and moderate exercise was linked with a stronger libido. Hackney hopes future surveys will reveal the "tipping point" when the amount and type of exercise begins to have a negative effect on the male sex drive.