Newbie question here...

When a club ride advertizes as a 15-17 or a 18-20 mph ride... do they mean your average speed including flats, hills and decents OR do they mean just your average speed you ride along flats (or rolling hills).

I ride about 17-19+ average when headed out on my regular ride from home that just has mainly rolling hills but has 3 "good" hills that drops my entire ride average to 13-15.

I don't want to join a club ride and be way over my head. Thanks to all!

Diana