I'm currently in the early stages of a relationship with a new man. He is in his mid-30s. We have had sex a couple of times and when he has been on top (which is my preferred position), he gets exhausted to the point where he has to stop completely. He will say he needs to take a break to get his breath back. He will be panting and sweating like someone who has just ran a marathon. This happens after about 2 minutes of thrusting from him at the most. He pleasures me in other ways, but it seems unusual to me that he gets tired so quickly during intercourse. He isn't overweight and doesn't seem to be outwardly unwell. He doesn't go to the gym or anything like that though. What would you expect to be a normal amount of time for sex to last when the man is on top?