Nudism and sex life!
I am not sure there is a negative impact. If you can have an erection with no shame, and your perception of yourself improves, I think we can be more affectionate in more scenarios, which equates to being more comfortable. As far as sex life, its another step in life. For me, I am uninhibted at home, its easier to have sex or explore with no clothes on. Real people, real situations.
Being nude whenever possible, privately and socially, is bound to have a positive effect on our sex lives. As well as providing opportunities, it encourages a healthy lifestyle, which keeps us fit, and in good shape. Feeling relaxed while naked, while remaining sexually aware, adds a touch of excitement to everyday situations. It works for me, anyway!
I don't know about easier to "perform" in bed, but I will say this: Although my nudist friends are not people I am sexually attracted to, becoming comfortable in those situations led eventually to becoming comfortable in sexually charged contexts also.