Whatever you do... DON'T get sucked in by all of your riding buddies who push the 53 all the time. 80 - 85 RPM cadence is just fine; find the gear that allows you to pedal at that rate comfortably.

Pushing a high gear ratio all the time = burning your knees up and potentially turning you into an invalid, which your riding 'buddies' wouldn't give a hoot about. Ride your ride, and don't get drawn into 'harder is better'... your knees will thank you later in life.