My first peer programming experience was exhausting. After 2 hours I was done for the day. After practicing for a few weeks, we could do around 4 hours split into 2 hour sessions without getting too tired. So it definitely has an effect to practice. Another positive aspect of it is (pretty likely) getting less distracted. You need a strong focus to concentrate on the task and the other person.

However, I think that peer programming does not work with everyone. Sometimes the peers do not match and getting work done is extra difficult. It also depends on the task. In my experience there were things that I could do better working alone, e.g. working on specification stuff like parsing a complex file format where I read a lot of documentation in the first place.

If you have someone to practice with, I think you could try to improve it and see how it works, but it should still be fun and not something you hate and you just need to do to improve.