Should I specify my interests in my CV, or is ‘sport and reading’ enough?

It’s better to describe in more detail which sports you play. That way, you can demonstrate a range of soft skills. Team spirit, for example, through a team sport, or ambition through athletics. If you mention the sort of books you like to read, you’ll give a better insight into your personality. And that’s exactly what the person you’re talking to is interested in.