Believe it or not, the interest section on your resume is valuable for several reasons
1) It is one of the few places where you can show a little of your personality
2) It is an opportunity to create a connection with the person reviewing your resume. If you are rock climber and they are a rock climber, they may be more likely to push you through the process
3) It gives the interviewer something interesting to discuss during the interview. Interviewers get tired of discussing mundane facts about your educational and professional background. They often prefer a more engaging off-beat discussion
4) Hiring managers like to hire people that fit the culture of the company. Your interests help communicate to people if you fit that culture.
So, don’t exclude your interest and be as detailed as possible. Don’t just write that you like “reading”. You should communicate that you like “reading Tom Clancy or Dean Koontz”